D&D Next: Mechanics

[h=1]Alignment[/h]

• "When you think of classic D&D what elements spring to mind?" -- "Alignment, Races, Classes, Monsters". Mike Mearls.
• "For now though, the 9 alignments seem to be back, and the Paladin WAS LG, no idea if that's an LG-only thing" [source]
• "The classic nine alignments are planned to be the default alignment assumptions." - Rodney Thompson.
• "However, we want alignment to be a tool, not a straightjacket, so the execution of those mechanics should serve that goal, and really only apply when dealing with the powerful, elemental forces of alignments, not someone who just behaves a certain way. Additionally, I believe we'll also want it to be easy for a DM to strip those mechanics out of his or her campaign, if the DM so chooses." - Rodney Thompson.

[h=1]"Three Pillars"[/h]

• "In general, we want to make sure that everyone has a baseline level of competence in all three pillars of play (combat, interaction, and exploration)." - Rodney Thompson
• "...when it comes to customization points, we want to let people choose what they want to focus on (be that combat, diplomacy, being the best liar ever, being a super stealthy thief, or whatever) and trust the baseline competence we've built into all characters to make sure everyone feels like they can participate." - Rodney Thompson
• "...while we might occasionally build in bonus skills into one class or another, we're trying to disassociate class and skills... we're looking at making it so that all of the backgrounds deliver an equal number of skills and traits, making it so that (with the exception of bonus skills built into the classes) all characters are on par with one another." - Rodney Thompson.

[h=1]Overall Rules Structure[/h]

• "Our primary goal is to produce a rules set that speaks to every incarnation of D&D. So if you are a diehard BECMI/Rules Cyclopedia enthusiast or have embraced 4th edition, loved 2nd edition, 3rd edition, or never moved on from 1st edition, we’re creating this game for you. Imagine a game where you can play the version of D&D you love best. And then imagine everyone plays at the same table, in the same adventure. We aim to make a universal game system that lets you play the game in whatever way, whatever style, with whatever focus you want, whether you want to kick down doors and kill monsters, engage in high intrigue, intense roleplaying, or simply to immerse yourself in a shared world. We’re creating a game where the mechanics can be as complex or as light as you want them. We’re creating the game you want to play." - Robert Schwalb.
• Snippets from a WotC designers' Google+ Hangout playtest confirm the existence of dwarves, lurkers, critical hits, paladins, clerics, trolls (which are vulnerable to fire in some way), clerics, and an unonsciousness status. Mainly no-brainers.
  • "Playtesting in the Lost Caverns of Tsojcanth. My dwarf just slew a lurker with a well-timed crit to save the swallowed paladin." - Monte Cook.
  • "Playtested in the Lost Caverns of Tsojcanth. My cleric burned several downed trolls before they could finish off the unconscious paladin." - Bruce Cordell.
• This Legends & Lore article by Monte Cook says: "...this sounds so crazy that you probably won't believe it right now—we're designing the game so that not every player has to choose from the same set of options. Again, imagine a game where one player has a simple character sheet that has just a few things noted on it, and the player next to him has all sorts of skills, feats, and special abilities. And yet they can still play the game together and everything remains relatively balanced. Your 1E-loving friend can play in your 3E-style game and not have to deal with all the options he or she doesn't want or need. Or vice versa. It's all up to you to decide."
• "To be clear, we're not talking about creating a bridge so that you can play 1E and 4E at the same time. Instead, we're allowing you to play a 1E-style game or a 4E-style game with the same rules. Also, players at the table can choose the style of character they want to play." - Monte Cook.
• "So, the game is actually a matrix of these choices, with some made by the DM and some by the players, which will end up determining the feel of the overall game and might allow the group to "emulate" a prior edition." - Monte Cook.
• "Players can pick their own style and complexity within a class. Think of it kind of like having a $10 budget to spend on lunch. Some people will go to a restaurant and buy a $10 lunch special. Someone else might spend that $10 by ordering a few different things off the menu, rather than a special. Someone else might take that $10 and go to the grocery store to buy all the ingredients for a recipe they like. The idea is to put everyone on the same scale, but then allow people to burrow into the level of detail they want. DMs have a similar process they can go through, adding optional rules to flesh out their campaigns. Those options can range from creating a unique list of races or classes for a setting, to adding in special rules for things like managing a kingdom or waging a war." - Mike Mearls.
• "We actually went back and played every major edition of D&D and used those experiences to help narrow down the absolute core elements of the game. If you removed those elements, it’s not D&D. Our list includes the six abilities, classes, levels, hit points, Armor Class, and a few other things." - Mike Mearls.
• "I can say that starting with the simplest base possible is likely a given, as it’s far easier to add complexity to a game rather than take it away." - Mike Mearls. It sounds like the core game will be very basic, with optional add-ons.
• Mike Mearls on the essentials of D&D: "The shared language: HP, AC, and things that lead to a shared culture.Shared stories: The Dread Gazeebo, the Head of Vecna, these things help make our common culture."
• Mike Mearls "For example, a mass combat expansion would have a basic, core system. Choose modules to play generals, etc. Are you seeing the mass combat from the top down, or from an individual's POV?"
• No explicit power sources. Moving away from jargon and keywords, towards natural language.

[h=1]Monsters[/h]

• "The Monsters are in the design teams hands now and we'll be moving to development in the next few weeks. What I can say about this goal that Monte is talking about is that we're working to provide the DM with really good world building tools. And it's important to provide information about the orcs place in D&D while making sure that a Monster remains relevant as the characters level up. They're might be an orc shaman, an orc champion or whatever for higher levels, but we also want the basic orc to be relevant at higher levels. We want it to be really easy for the DM to open the Monster Manual and drop an orc or iconic monsters into the game." - Jeremy Crawford
• "While many DMs want to build monsters using the target numbers-based system that 4th edition uses, some DMs may want to build their monsters like PCs, adding levels of cleric onto orcs to create enemies that also have many class features. Some DMs may want to use templates to create everything from a fiendish hobgoblin to a vampiric half-celestial animated chair. So we'll need to find ways to support those needs, without mandating them." - Rodney Thompson.
• "In general, I think that monsters should do what fans of D&D lore expect them to do, and if that means being really scary mechanically then so be it. I think there's room in the game for monsters that simply are more dangerous and deadly than others, just as I think there's room in the game for monsters whose purpose is to be interacted with, not fought. I also think it's good for monsters to exist that you don't want to face in a straight-up fight, but that you need to be prepared for or figure out a clever way to outwit rather than going in spells a-blazin'." - Rodney Thompson.
• Minions: "One of the things we're exploring in the game is what we refer to as a bounded accuracy system. Effectively, we're looking into whether or not we can strip out the assumption of accuracy and defense scaling by level, and let progression rest largely within the scaling damage, hit points, and capabilities of both characters and monsters. When you have this, any monster whose hit points are less than the damage you deal is, effectively, a minion. Thus, we might not need a specific minion rule, because we would simply design monsters with hit points that rest below average damage for certain levels and let that take care of it (in other words, we do want monsters in the game that do what minions do for us). At the same time, since as the player characters gain levels their damage numbers are going up, monsters that previously were not "minions" become "minions" by virtue of player damage outstripping their hit points. Since AC and attack bonuses aren't automatically scaling up, the orc that you fight at 1st level that took three hits to kill may only take 1 hit to kill at 6th level, making it a "minion" for heroes of that level." - Rodney Thompson.
• Solo Monsters: "As far as "improving solo monsters" goes, there are some things we have learned over the course of the last few years that are vulnerabilities that can plague solo monsters; being taken out of the fight by conditions like daze/stun/dominate, or lasting too long so the fight starts to drag, running out of tricks to pull, being challenging for the DM to run, etc. However, not all of these are exclusively monster issues, and some can be solved by changing things elsewhere in the game. For example, if we used something like the "hit points as a threshold for affecting monsters" mechanic that Mike described for "save or die" spells in a recent Legends & Lore column, we can cut down on some of the challenges solos face because of conditions." - Rodney Thompson.
• Morale: Looking at re-introducing morale rules into the game. - Robert Schwalb
  • "In fact, I can imagine most monsters, once they’ve lost about half their numbers, will say screw it and run away. It just makes sense. Evil doesn’t usually place a lot of stock in honor and fighting to protect their fellows." - Robert Schwalb
• Monster Advancement: "Truthfully, we're not far enough into the game's design cycle to put too much work into monster advancement; up to this point, we've been more focused on creating the base versions of the monsters, making sure they work, etc. That said, I think we'd like to have many methods of advancing and altering monsters. Personally, I loved the idea behind templates from 3rd Edition, and really like the way we handle monster themes in 4E as a method of tinkering. It's also pretty easy to just have rules for scaling up a monster's raw numbers. Ideally, we're going to have a broad spectrum of ways for DMs to modify and scale up monsters, letting the DM choose his or her preferred method." - Rodney Thompson.
• Monster Types: A hobgoblin has a "beastmaster" variant or class (unclear). [source]

[h=3]Monster Design Articles[/h]
[NEW 18 JUNE] Mike Mearls' articles on monster design can be found here and here.

• The first article contains a sample hook horror and emphasizes monster deign in terms of both story and numbers.
• Strength in numbers: with the flatter math, large numbers of monsters are more dangerous and relevant to higher level characters than before; and vice versa. So the red dragon is a challenge to a high level party, but can still be taken down by 200 militiamen. A party of adventurers can handle an orc warband, but not an orc army.
• Complexity: special abilities are moving to the monster chieftain types, keeping the "mooks" simple.
• Nonhumanoid monsters will be more complicated.
• "On top of that, one of our goals is to create a general set of stunts that monsters can attempt, usually drawing on their high ability scores, size, and so on. For example, abilities such as stomp, fling, and bull rush might exist as maneuvers that any monster can attempt in the tactical combat module. Rather than hard code a fling ability into the hook horror, a DM can either plan on using it based on encounter design or improvise it during a battle."[comment] END CODE DOWN FROM HERE[/comment]

[h=1]Advancement[/h]

• "Instead of the fighter getting a better and better attack bonus, he instead gets more options to do stuff as he goes up in level, and his attack bonus goes up at a very modest rate. I think it offers a better play experience that the orc/ogre can remain in the campaign, and people can know how the monster would work from a previous experience, but they remain a challenge for longer." - Monte Cook
• Character advancement should go as fast as the group wants it to go. Meaty rules in the DMs book to adjust that.
• "Additionally, we're looking at having the classes gradually layer in more capabilities over the first two or three levels, rather than providing a large number of class features at level 1, so that players new to the class have a short period of time to learn the basics of their class through play. Experienced players could simply start at 3rd level if they want to leap right into a more advanced starting experience." - Rodney Thompson.
• Things don't scale so dramatically.
• Makes equipment interesting for longer, monsters challenging for longer.
• Ablity scores don't advance as quickly.
• Attack bonus scales less, so ability score means more.
• "...we're looking at a bounded accuracy system where accuracy (of everything, from attacks to spells) does not automatically go up with level." - Rodney Thompson.
• Different reward options: monsters, quests, roleplaying.
• Castles & Followers: "We can also have other options, like building a castle, having followers and vassals. We can build that into what high level characters get." - Monte Cook.
• 0-Level Play: "While I don't think level 0 play will be an assumed part of the core game, I think it's perfectly viable as an optional rules module. However, I'd also like to point out that themes do a lot for creating the kinds of character history." - Rodney Thompson.
• "Another thing we're looking at is the way we word certain abilities, making sure that disparate classes work well together. For example, instead of the fighter having to spend a single action to make multiple attacks, we might say that the extra attacks that the fighter gains as he gains levels are effectively free actions that the fighter takes on his turn. Thus, if my fighter/wizard picked up an extra attack through his levels of fighter, he might be able to cast a spell as his main action and then still get his extra attack, giving him the benefit of all of his class levels." - Rodney Thompson.

[h=2]Multiclassing[/h]

• Multiclassing: "...here's what we have in mind. When you gain a level, you can choose any class and gain a level in that class, much in the same way that it functioned in 3rd Edition. Of course, those of you who play or played 3E know that there can sometimes be issues with this, and if you aren't careful you can build a character that struggles with effectiveness at higher levels. However, there's a lot of good that comes out of this system, including organic character growth, expansive character building options without the need for large swathes of material, and the ability to express your character's specialties through a unique mix of classes." - Rodney Thompson.

[h=1]Magic Items[/h]

• Magic Items - iconic. Flame-tongue, holy avenger, wand of wonder.
• Cap on stat boosts from items.
• Gauntlets of ogre power exist.
• Magic items no longer part of essential progression mathematics.
• "We're running with the idea that magic items are special and not bound to character progression."
• Magic items are possible, but difficult to create by PCs.
• Not balancing the classes based on the expectation of magical items.

[h=1]Skills & Ability Scores[/h]

• Skills & Ability Scores: the "Reimagining Skills & Ability Scores" seminar at DDXP was very informative. Much of the info here came from that seminar, but read the full transcript for actual quotes.
• "...ability scores were the same old 16 (+3), so still 3e/4e stats. Attack bonuses/AC were higher = better, so no THAC0." [source]
• The idea is to make ability scores have a big influence.
• Half-orc gets +1 STR. Fighter gets +1 STR. Generally race gets a +1 bonus.
• Basic is 4d6 drop the lowest for ability scores, but other options available.
• The DM can just say "yes, you have 17 STR, you burst through the door" - getting past some of the mundane rolls and not tie up game time with that. No roll to see if there's a gem in a jar, but an INT roll to find a hidden compartment. Someone with 15 STR can just jump over a pit with no roll.
• Heraldry mentioned as a skill. - D&D Podcast
• Skill challenges - "I want them to die in a fire".
• Complex skill checks within the narrative.
• Describe actions, but can just make skill checks if you want.
• Encourages narrative ways of, say, crossing the pit, rather than a simple skill check.
• A class or theme might give a bonus to a skill, but no actual skill list. DM calls for relevant ability score check, and if you have a class or character feature that gives a bonus to that action, you add it in. Makes possible for open-ended, infinite set of specific flavorful micro-skills.
• Easy to completely leave skills out of the game.
• "Advantage" is something a DM can hand to a player who uses a good description.
• Option to roleplay and ignore ability scores.
• "Some characters had bonuses to certain actions, like the rogue being good at bluffing, the wizard using arcana to detect magic/identify items, the fighter kicking down doors left and right, and so forth. It seemed very simple, almost ad-hoc..." [source]
• Saving throws are back.
• Skills are ability checks.
  • A skill is essentially a notation to a stat. For example, STR 15, and bonus to opening jam jars because you're just really good at that particular thing.
  • [NEW 16 MAY] "The fundamental design shift rests squarely on moving task resolution from skills (make a Climb/Athletics check to climb) to the abilities (make a Strength check to climb). At this time, the next iteration regards abilities as a combination of both raw talent and training, and it differs from the 3rd Edition model, which made, at least in practice, abilities raw talent only. This means if your character is smart (high Intelligence), you probably know a lot about lots of stuff. This means if your character is strong, you’re probably good at climbing walls, jumping across pits, and swimming through rough water." - Robert Schwalb.
  • [NEW 16 MAY] "A skill always refers to a specific task: climbing, charm, deception, and so on. If you have training, you get a +2 bonus to any check made that involves that task. The bonus typically increases based on your class (rogues are good with skills) or, if you gain training in the skill again, increasing the bonus by 1 for each instance." - Robert Schwalb.
• CHA is linked to fear and charm effects.
• [NEW 15 MAY] "...while we might occasionally build in bonus skills into one class or another, we're trying to disassociate class and skills... we're looking at making it so that all of the backgrounds deliver an equal number of skills and traits, making it so that (with the exception of bonus skills built into the classes) all characters are on par with one another." - Rodney Thompson.
• [NEW 16 MAY] On Losing Skill Lists: "Although many see skills as empowering, offering customization options and character definition, in my experience, skills actually constricted game play so players tended to operate only within the bounds of the skills their characters possessed. If you tried to do something that wasn’t a skill, the DM might fall back on an ability check, which in both 3rd and 4th Edition wasn’t great since you didn’t get to add your skill/training bonus to your check result. Rather than improvise and come up with something unexpected, I found, in my own gaming experiences, players combed the skill lists on the character sheet to determine what they could and couldn’t do when presented with a challenge." - Robert Schwalb.
• Skills are delivered via backgounds and themes in broader packages; " Finally, since we’re delivering skills by way of backgrounds, the skills we introduce to the game point back to a larger concept such as Sage, Thief, or Mariner." - Robert Schwalb.
  • [NEW 16 MAY] "As it currently stands, your background grants you four things—either skills or traits. A skill always refers to a specific task: climbing, charm, deception, and so on. If you have training, you get a +2 bonus to any check made that involves that task. The bonus typically increases based on your class (rogues are good with skills) or, if you gain training in the skill again, increasing the bonus by 1 for each instance." - Robert Schwalb.

[h=4]Sample Skills[/h]
[NEW 16 MAY] This skill was posted by Robert Schwalb in this column.

Trained in Charm (Charisma): This skill applies whenever you would befriend, seduce, or otherwise charm another person.

(As noted above, this would be a Charisma check with a +2 bonus).

[h=2]Traits[/h]

From this column by Robert Schwalb:

• Where skills can improve your chances for success in specific situations, traits are minor benefits that usually interact with specific tasks. A trait doesn’t grant you a bonus. It just lets you do something or speaks to your character’s place in the world. Here are two example traits:
  • Extra Language: You are fluent in a language of your choice.
  • Workshop: You own a workshop somewhere in the world. Work with your DM to determine the best possible location for this shop. You have everything you need to produce the items you have learned to craft.

[h=1]Feats[/h]

• "As for feats, we want them to have a significant impact on how your character plays. We also want feats to allow some complexity customization. If you want to play a simple, streamlined character, we want to provide plenty of simple, streamlined feats for you to use. If you want a complex character, take complex feats. Either way, we want you to feel like taking a feat really affects the way your character plays." - Rodney Thompson.
• [NEW 15 MAY] "...we want themes to be things that transcend class ... there are a lot of exciting possibilities in the strange combinations ... . Tying feats to specific class features limits those possibilities, which is something we want to avoid. Plus, we'd like to make it so that players don't feel like they have to chase certain feats to be able to fulfill the promise of their classes."

[h=1]Equipment[/h]

• Equipment - making it a bit more important.
• Moving from gold to silver standard.
  • "Gold is the new platinum, and electrum is back. Electrum was explicitly found. EL-ECT-RUM." [source]
• Mundane wand is 100gp, like fighter's scale armor.
• Weapons defined by categories not specific names. You're good with all axes, swords, bows, for example. Fighter doesn't find a cool axe but can't use it because he didn't choose to be an axe guy - you're good at all weapons.
• Accuracy and damage changes by weapon. Also damage types (slashing/piercing, etc.).
• "There have been many times since the inception of 4E where we'd wished we had some kind of damage type for physical damage, a point that was driven home especially well when we did the design and development of the Gamma World game, which does have a physical damage type. I think the step that previous editions could have taken, but didn't, is to treat slashing, bludgeoning, and piercing damage types just like acid, cold, fire, etc. damage. That way, weapon users get a few more interesting choices in the weapons they wield, just like spellcasters have when making spell selection" - Rodney Thompson.
• Weapon specialization benefits - some are like at-will attacks.
• "Weapons were mostly similar, but proficiency bonuses seem back. We didn't really get to look at a list or anything. Simple/Martial split, light weapons were mentioned. I'm thinking a 3e/4e hybrid for weapons. Never saw any reach weapons... damage types did seem back but I can't be sure." [source]
• "One area where we might make some tweaks is trying to level the playing field on a lot of common weapons, because for many players, a weapon is an aesthetic choice, and it's kind of a drag to pick a weapon for aesthetic reasons only to find out your character is somehow hampered because you didn't make another, less aesthetically pleasing choice. Also, yes, right now we're looking at typing weapon damage, just like we do with spell damage. So, a mace might do 1d8 bludgeoning damage, for example." - Rodney Thompson
• Crafting: "The goal is to make sure the rules for crafting things are present, and that you can opt into being a craftsman if you want as a player, but that doing so doesn't consume a significant portion of the resources you need for adventuring. We've tinkered with putting it in themes, for example, as a benefit that you just get." - Rodney Thompson

[h=1]Combat[/h]

• Combat: Gridded combat in core rulebook. but as an optional module.
• "Right now, the design of the game does not assume by default that you are using a battlemat and miniatures when adjudicating combat, and as such we feel confident that spells like cone of cold could be cones, and lightning bolt could be a line, without having too many problems. However, when we present the rules for using a grid for combat, we're going to want to present ways to convert those spells into the more grid-friendly areas like bursts and blasts. We can also present the grid-based versions of bursts, cones, lines, etc. found in the 3.5 Edition of the game. Moreover, we don't even have to limit ourselves to a square grid, and could present the rules for playing on a hex grid too, allowing each group to determine what fits their needs best." - Rodney Thompson
• Additional tactical rules modules.
• More gritty than 4E but not as gritty as OD&D.
• "Measurement is in feet." [source]
• "...charging kinda sucks. Extra damage, but you take a minus TO HIT as well as to your defenses. Very risky." [source]
• "Advantage" is something a DM can hand to a player who uses a good description.
• "...the Rogue had "weapon finesse", but his damage was still Str-based. The attack roll seemed to be mostly Strength + a hidden weapon proficiency bonus, seemed to be +2 for everything+masterwork if any. It was modifier based, not score based" [source]
• [NEW 16 MAY] Damage Resistance: "Also, I got to test the DR rules when the players had to cut open a dead wererat's stomach to find a gem it had swallowed. That was not how I expected to test those rules." - Mike Mearls.
• [NEW 16 MAY] Movement & Positioning: " I'm really not a fan of giving people extra turns in addition to their own turn. I think it really slows the game down. For movement and positioning, the goal is to focus more on terrain and interesting things to move to and around, rather than flanking and such. There are off-turn actions in the game, but the philosophy now is to have them eat into your turn or have something you have to set up. For instance, instead of everyone automatically getting opportunity attacks, a character might need to take a feat or choose an ability that basically says, "If you make a melee attack on your turn, you get one opportunity attack for the next round. A rogue might have this - you can move away from an enemy that moves next to you, but you lose your move on your next turn." - Mike Mearls.
• Attacks of Opportunity/Area Effects/Flanking: "The answer is yes to all three, but in different ways. We already have area effects in the game, mostly in the form of spells. We have some ideas about flanking, but those ideas are more likely to show up in a tactical combat module that would sit alongside guidelines for using the grid more effectively. As for attacks of opportunity, a big piece of feedback we're getting from the playtesters is that it's too easy for spellcasters and ranged attackers to get away from melee combatants, so we're discussing some ways to address this problem with a modified version of opportunity attacks. The goal is to keep things streamlined and fast (we're getting a lot of positive feedback right now on the speed of combat, and we want to keep it that way), but we do want to explore something that keeps characters from fleeing melee with no consequences." - Rodney Thompson.
• [NEW 19 JUNE] Facing Rules: "Perhaps one of the more exciting portions of this module that we're tinkering with is facing rules. Mike has drafted some very tight, clean rules for facing that should add a lot of tactical depth to combat, and make movement and positioning even more important than ever." - Rodney Thompson.

[h=2]Hit Points[/h]

• "Hit points are a great example of an area of the game that we don't think needs any real changes. They have remained consistent in their use throughout the editions, and we think they are one of the touchstones of the game. We might tinker with acquisition and recovery of hit points, but the basic concept of hit points should remain unchanged." - Rodney Thompson
• Healing: "First, I don’t think that clerics being the sole healers is something I’d consider a common trait of D&D throughout the ages; the bard and the druid classes were both capable healers in previous editions. Though the cleric was arguably the best healer in certain editions, others could fill that role; 4E just went further and standardized healing mechanisms between all healing classes. As I mentioned in the first question above, we also think there should be some self-healing or non-magical healing." - Rodney Thompson.
• "This is a great example of where we can offer lots of options to create the kinds of games that any individual DM and his or her players want to play. Want to run a game where players are always healed up to full hit points between fights? No problem; we’ve got rules for that. Want to run a game that is super-deadly with disposable characters? We can do that too, just by tweaking things like hit points, availability of self healing, and so forth." - Rodney Thompson.
• "...at level 1 most characters had about 15 HP" [source]
• "- Con score = ded [sic]. You make a Con save to avoid dying. Fail, lose 1d6 HP. Make 3 and you stabilize. So, make, fail, fail, make, make, you're stable but down 2d6. Makes being dying kinda tense." [source]
• "Ohh, resting. You get 4 rests per day; 2 short 10-minute ones, a 1-hour one, and an 8-hour one. 10-minutes give you back your level in HP, the 1-hour lets you get back 1/2 your hp OR re-prep some spells (one or the other, caster-bitches!), while an 8-hour gives you back both 1/2 HP and all your spells. There were no healing surges in sight." [source]
• "Criticals were 4e/3e hybrids; roll a 20, do max damage AND roll to confirm. On a success, extra damage equal to your class' HD; rogue 1d6, fighter 1d10, etc." [source]
• Critical Fumbles/Injuries: "Those are two great examples of things that probably wouldn't be core assumptions, but could live as modules, albeit in a core book." - Rodney Thompson.
• [NEW 21 MAY] Mike Mearls talks about hit points and hit dice in detail here:
  • HP clearly defined as physical injury, experience, and luck/fate.
  • Over half HP is a scratches and bruises; under half is noticeable injuries; less than zero is a serious injury.
  • Hit Dice (Fighter d10, Rogue & Cleric d8, Wizard d6) represent the amount you heal with natural rest.
  • Potions and spells heal HP directly.

[h=2]Conditions & Statuses[/h]

• "So talking about things like stun, daze, and immobilzed right? Currently we're in the area that the effect should be relevant to the spell or power. For example there might be a power word stun spell that explains what stun is and goes from there. But we're probably not going to have too many abilities or spells that would do something like that. We've pared down and increased the list of status effects, back and forth."
• [NEW 16 MAY] Conditions: "We've been discussing conditions quite a bit lately. They're certainly in the game. I'll be revising them this afternoon, in fact. We're fans of conditions that make sense both as game mechanics and as something in the world. Prone, for example, is a useful game concept, and it matches what's going in the story. You're knocked on your butt!" - Jeremy Crawford.
• [NEW 16 MAY] Conditions: "We're trying to keep the list of conditions slim and make it apply to things that are obvious changes in the world. For instance, right now invisible and ethereal are on the list of conditions. We also added intoxicated. Basically, what are things that when they happen to you have a clear effect on how you interact with the world? Here's another thing - with stuff like paralyzed, we're dealing more in describing what happens rather than trying to make everything mechanical. So paralyzed says that you can' t move your limbs. Spellcasting specifies that you need to move your arms to cast a spell. Thus, a paralyzed creature can't cast spells. The idea is that we give the DM clear mechanics, but also make it clear what's happening in the world so the DM can make any judgment calls as needed." - Mike Mearls.

[h=2]Action Types[/h]

• Reaction/Interrupt Actions: "...off-turn actions are one of the primary sources of game play slowdown—not simply in their resolution, but in the player's need to keep them in his or her mind all the time... Going forward, I think we'll want to address the challenges associated with off-turn actions in a couple of different ways. First, I think we'll want to be more cautious with how many we inject into the game. In order to retain the benefits of the "active defense" side of off-turn actions, we can look to saving throws as a method of providing that feeling, and then build mechanics that ride on top of the saving throw if the player chooses them." - Rodney Thompson.
• "As of right now, we have a system that states that on your turn you can take one action, and then move up to your speed. Most everything is just an action; attacks, casting spells, activating magic items, etc. "Moving up to your speed" can also cover things like climbing, jumping, and standing up from prone within that movement. We believe this is going to accomplish our goal of making combat move faster across all levels, being easier to teach to new players, and also making sure that the kinds of effects we're putting into the game are big, meaty and significant so that you really feel their impact." - Rodney Thompson.
• [NEW 21 MAY] "I’d like interrupts to serve either two purposes. First, I think quick, simple interrupts that boost a defense are OK. For instance, an interrupt that boosts your AC or reduces damage you take. You resolve it quickly and it doesn’t slow the pace too much. For more complex interrupts, like those that require die rolls or decisions, I’d prefer the interrupt to take away part of your next turn. That way, the total time it takes to go around the table remains relatively constant. In essence, you’re taking your action ahead of time rather than getting two actions during a round." - Mike Mearls.

[h=1]Mike Mearls: Ask Me Anything[/h]
[NEW 18 JUNE] Mike Mearls held a long "ask me anything" session on Reddit, the overview of which you can find here. Below is a compiled summary of information from EN World member GX.Sigma:

I have compiled a list of new information gleaned from the AMA. The indented bullets are quotes.

• Core “swarm” rule for large groups of enemies
  • "I'd like to incorporate a core "swarm" rule into the game, an easy way for DMs to group up monsters into single attacks. For instance, something that lets you combine X attacks into one die roll, with some small amount of damage even on a miss to make that an appealing option. Hopefully, that solves the rat issue and also the humanoid horde issue at higher levels."
  • "The orcs can all hit as often as they should, but it might be better/faster/easier for the DM to resolve their 18 attacks in fewer die rolls."
• Considering changes to skill mechanic
  • "We're looking at skills right now and trying to determine if skills make you better than you are (a flat bonus that adds to your ability check) or strictly make you good (a flat bonus that takes the place of your ability modiifer). So, the 8 Wis rogue with perception training might just be at, say, +5, rather than at +3 added to a -1 Wis check."
• Conversion guidelines, not necessarily a direct conversion manual
  • "The trick with direct conversions is that it requires a lot of time and can easily lead to broken stuff. That said, we're starting with the most popular stuff from each edition, and we should have general conversion guidelines that let you do some conversions yourself."
• Considering Warlord as theme
  • "The warlord is tricky, because I think a theme might work pretty well for it. I can see wizards or fighters or rangers as warlords. That said, we're not wedded to that. It'll depend on what we see as the key features of a warlord and the best way to express them."
  • "It'll really come down to how it feels in play. I wouldn't be surprised if we tried designing it both as a class and as a theme to see how it plays out."
• Maneuver system details: anyone can take (theme related), fighters are best at them
  • "For the fighter - lots of feedback that it needs more. We're working on a set of maneuvers that the fighter and other classes can access through themes."
  • "Anyone can take maneuvers."
  • "We're introducing a system of combat maneuvers, and we're also looking at stuff like the Book of Nine Swords, psionics, and the focus feats from the 3.5 PH 2 for inspiration for martial characters. In many ways, the key is finding a way to express those options that preserves the feel and flavor of D&D while also keeping the classes unique."
  • "How would this strike you - would you be cool with a maneuver system that also included tactical plans, and if fighters are the best at using maneuvers, a fighter with a warlord theme feels a lot like that class in play?"
• Organizing rules modules
  • "Yes, the idea is to give each one a clear identity/name, and then if there are some logical groupings present those as campaign recipes."
• Random HP and fixed HP both options
  • "Random HP will be an option alongside fixed HP. The key to Con is that adding the bonus at each level can overwhelm class contribution to total HP. We need to find a middle ground."
• Level 20 cap, then optional epic level advancement?
  • "We're looking at capping at level 20, but giving a set of options for uncapped advancement beyond that."
• Spellcasting monsters will be made easier
  • "I like monsters with spells, especially NPCs. What I'd like to do is develop a slimmed down spell format that lets us place spells in a stat block in a concise, easy to use manner so that DMs can run them just like any other creature."
  • "A lot of common spells - fireball, hold person - are no more complex than the typical monster special ability, so I think we can pull this off."
• Starting equipment packages based on background and class
  • "We're actually looking at making buying equipment optional. Instead, you are given a starting package based on background and class."
• No alignment mechanics in core
  • "The goal is to remove mechanics from alignment. It's a key part of the world, but not the rules or spells."
• Healing rules far from done
  • "The healing rules are going to get a complete overhaul."
  • "The idea behind making [the healer’s kit] an item was to make it something anyone could take. One direction we're thinking of taking is making a cleric's healing a separate ability from spells, so that we can give more healing without also having to give more spells in total."
  • "Healing is definitely going to get a number of dials to let DMs tweak it to fit their games. You can imagine a range that starts with "Festering wounds and missing limbs" on one end and has "Sleep cures all ills" on the other."
  • "In the closed playtest we ran before the open one started, we had a lot of feedback that healing was too limited. With hit dice, we tried to introduce a more robust mechanic for natural healing to give characters more healing overall. They are supposed to change the game so that the characters aren't as reliant on the cleric, but so far the rules don't seem to work well enough. We will be revising them for the next round of testing."
  • "One of the key hang ups we have with healing is trying to find a way to make the cleric optional. So, we're definitely aiming to make it so that you can remove classes, races, or entire types of magic without screwing up the game's balance. I think restricting that sort of thing is one of the ways that DMs like to make unique campaigns, so we want to allow for that."
  • "The feedback on long rests has primarily been that they are far too forgiving. It feels lame that the party can be on the edge of death, sleep for eight hours, and bounce back up to full strength."
• Multiple XP options, including treasure XP and story XP
  • "The XP system is the kind of thing where I want to do a few different systems and have the DM pick one (XP for treasure, XP for killing, XP for meeting story goals, etc) to establish the tone for his or her campaign."
• Morale and reaction rolls!
  • "Yup, you can expect both in rules modules. I wrote a set of morale rules for tactical play, and I expect we'll include reaction tables for our interaction mechanics."
• Opportunity attack if you leave melee
  • "Yes, we're looking at adding a free attack against you if you try to leave melee."
  • "Keep in mind that our goal for adding a mechanic like this would be to keep it very, very simple. We are 100% NOT going to give you a long list of things that provoke. It would be moving away from an enemy and nothing else."
  • "We actually did some research on this, and even back in AD&D there were some pretty serious penalties for trying to move away from someone in a fight. IIRC, in AD&D the attacker got a +4 bonus to the attack and you couldn't use your shield or Dex bonus to AC."
  • "We're strongly considering adding a free attack if someone breaks away from a melee. The playtest feedback has been a little soured on letting people move around without consequence. However, the rule would be much simpler than attacks of opportunity - likely it'll be that if you start your turn in someone's reach, they get an attack on you if you try to leave their reach using an action to withdraw."
• Core leans towards Combat as War, tactical rules module is for Combat as Sport
  • "If you look at where we are right now, the core game leans more toward combat as war. Fights are fast and reward people who can get advantage or force the monsters to commit piecemeal. You can become overwhelmed if you let all 10 goblins rush you at once."
  • "For combat as sport, that is 100% where the full blown tactical rules module is aiming. This is one of those areas where groups have very different tastes, and modularity should help us bridge that gap if we do it right."
• Armor is getting an overhaul
  • "We're completely re-working armor. We're bulking up heavy armor, giving medium armor a better definition, and slightly pulling back on light armor."
  • "Heavy armor allows no Dex bonus but has a high base value. Heavy armor always gives disad on attempts to be stealthy."
  • "Medium armor has +2 Dex max or no Dex allowed. It sits below heavy armor. Classes like the ranger and barbarian are proficient with it. Some medium armors give disad on checks to hide or move silently. Basically, if you play a ranger or barbarian, you can either junk Dex and take a "heavier" medium armor or take a lighter one that lets you be stealthy."
  • "Light armor allows full Dex and has no stealth drawbacks."
• Return to the Celtic bard of 1e
  • "The first pass on bards is going back to their Celtic roots while also looking at making a jack of all trades mechanic that doesn't make the bard second best at everything. It's still early, and the final design might be much different, but I really want to give the bard something unique that really speaks to their roots."
• They get the message about the rats.
  • "You could say it was a good idea in that it gave us a lot of immediate, aggressive feedback to never, ever, ever do that again and to immediately, right now, fix that."
• There is a background that gives you noncombatant lackeys
  • "In this week's playtest, Chris Perkins took a background that gave his fighter three combat-useless lackeys. They carried his gear for him. When the party was ambushed by an ogre, in a rare fit of consideration he ordered the lackeys to run for their lives. They beat his fighter's initiative and did indeed run off - while still carrying his crossbow, shield, and other gear."