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Stalker0's Obsidian Skill Challenge System (Update: Version 1.1) Now with PDF!!


Stalker0’s Obsidian Skill Challenge System

UPDATE!! The system has now moved to Version 1.1. The changes are small, here you go.

Changes from Version 1.0
1) Critical Success now gives 2 successes, instead of providing rerolls.
2) Table 2’s victory and partial victory numbers have been changed for a 2 person challenge.

UPDATE!! There is now a beautiful pdf version of the system, which is far easier to read than the forum. So save your eyes and take a look! Its at the bottom of this post

Welcome to the latest in my attempts at a new Skill Challenge System for 4th edition! Unlike my previous skill challenge ideas, this is a complete revamp from the standard system. So, the first question is who should consider using this system?

Consider using the Obsidian System if you believe in the following:
1) Players should always be included in skill challenges, but shouldn’t always get to use their best skills. A social character should shine in social encounters, and an athletic character should shine in athletic encounters.
2) Players shouldn’t feel that their participation is actually hurting the party’s chances of succeeding at a challenge. Players should always feel that they are helping the challenge, even if it’s to a smaller degree than a character with better skills.
3) A skill challenge should work as a decent encounter, but be easily scalable to a much longer and epic scale.
4) Players should spend more time describing their actions, and less time trying to find ways to use their best skills.
5) The skill challenge math should be solid enough to allow DM tweaking without causing problems.
6) The standard skill challenge system for whatever reason just isn’t for you.

If you’re still reading, here’s the deal. I will post the basic system in the first post. I will then post more advanced options for those who would like to use them in the second post. And then in the third post I will go into a detailed discussion of how and why the system works like it does. So basically, if you’re not into the nitty gritty just read the first or second post. The deeper you go, the more technical it becomes.
First of all, I need to give a special shout-out to Fredrick Svanberg. He was the first one to create the idea of doing skill challenges in rounds. From that idea, I have created a system I hope many can enjoy.

The Basic Skill Challenge
3 Segments: Every skill challenge consists of three segments. Each segment can last as long as the DM desires. For many challenges, a segment will be a single round. In others, it could be an encounter or several hours of work. During each segment:

1) Each player describes an action that his character is doing, whether it’s tumbling past a guard or talking with a duke. Players are free to describe actions that directly contribute to a skill challenge, or that simply help their fellow party members succeed. Both actions are considered equally important for the challenge.
2) The DM and the player work together to decide the right skill check for the action. In general, a player should be using skills that fit the challenge type (see Types of Challenges below) though the DM is the final judge whether a certain skill can be used.
3) If the player gives a particularly good description or role-plays well, the DM can give him a +2 to the skill check.
4) All players roll their skill checks versus the DC of the challenge. The DM counts up all of the successes that are made.
5) Steps 1-3 are repeated for the second and third segments of the challenge. The DM totals up all of the successes made, and then determines whether the party failed, obtained victory, or only obtained partial victory. See the “Winning and Losing” section below or more information.

DM NOTE: “DON’T CHANGE THE NUMBER OF SEGMENTS”. Increasing or decreasing the number of segments will have a very large impact on the system, and is not recommended. If you wish to have a longer skill challenge, take a look at “larger skill challenges” listed in the advanced options.​

Player Options: While playing in a skill challenge, players can use the following:
Bold Recovery: A player may spend an action point to reroll a skill check they have made, before they might know if the roll was a success or failure. The player must take the result of the reroll. If the skill challenge is particularly long, the DM may grant the players the option to use additional action points.

Critical Success: A natural 20 on a skill check is an automatic success. In addition, the player receives one additional success.

Primary Skill: For most challenges, the DM assigns one or two skills as the center point of the challenge. Players using that skill receive a +2 to their skill checks. Example: In a negotiation with a Duke, diplomacy would be the primary skill. In a scene where the party sneaks into an orc camp, stealth would be the primary skill. If the players were researching a secret from ancient arcane texts, arcana would be the primary.
DM NOTE: Primary skills are designed to encourage players to use the “the right skill at the right time”. Further it allows players with weaker skills a chance to have a decent skill check to make. However, not all skill challenges must have primary skills. If you do use a primary skill, make it well known to your players.​

STOP!!! If you’re a player, that’s really ALL you need to know to use this system, really. Feel free to keep reading, but note that most of the further information is about setting up a skill challenge.

Determining Skills Allowed and Setting Difficulty

What skills to allow?: One major difference between the standard 4e skill challenge system and the Obsidian System is that in the standard system, all players are assumed to use their best skills in the majority of skill challenges.

This is not the assumption in Obsidian. If players are in a social type challenge, they are expected to use social skills for example, even if they aren’t the best at it. This gives players that are good at certain skills a chance to shine and also lets each player roleplay their character at their best and worst moments. In general, use the Challenge Type (see below) to determine what skills to allow players to use. However, in some cases a player may make a very good case to use a different skill. As the DM, feel free to allow new skills, especially for creative, innovative uses.

As a good rule of thumb, only allow a player to use a nonstandard skill once per skill challenge and only if the player is creative with the skill.

Example: During a chase scene (a physical challenge) the rogue asks the DM if he can use bluff (a social, not a physical skill) to psych out the guards and escape. He gives a really good description of what he wants to do. The DM allows it, but for the rest of the challenge encourages the rogue to use physical skills (like acrobatics).

DM NOTE: “Why Intimidate is not a bad skill!” There are some skills that DMs have trouble relegating in their skill challenges. For example, if the party is in social challenge with a noble, the DM might think that intimidate is just going to anger the noble and so shouldn’t be used for the challenge. Whenever possible, try to think broadly when considering skills. For example, while a player directly intimidating the noble might not work, intimidate may work in a more subtle way. For example, the noble raises his voice and yells at the party, trying to get an advantage. However, when he looks over at the intimidating demeanor of a PC, he realizes such tactics won’t work, and he backs down (the player just rolled a success using intimidate). As a DM, if a player is trying to use a social skill for a social challenge, work with him to create a skill use that fits your story and lets the player use his skill.​

Setting Difficulty: A standard skill challenge’s level is the same as the party’s. Table 1 below gives the DC’s for the skill challenge at each level. If a DM wishes to change the difficulty, a +1/-1 to DC changes the difficulty of the challenge by about +/- 10%.

Table 1. Difficulty Class at Each Level
Level DC
1	18
[b]2	19[/b]
3	19
[b]4	20[/b]
5	20
[b]6	21[/b]
7	21
[b]8	23[/b]
9	23
[b]10	24[/b]
11	24
[b]12	24[/b]
13	24
[b]14	26[/b]
15	26
[b]16	27[/b]
17	27
[b]18	28[/b]
19	28
[b]20	29[/b]
21	30
[b]22	31[/b]
23	31
[b]24	32[/b]
25	32
[b]26	33[/b]
27	33
[b]28	34[/b]
29	34
[b]30	35[/b]

Winning and Losing
Once the DM has totaled up all of the successes for a challenge, he compares the total number to Table 2 given below. The table shows how many success rolls the party needs for partial or total victory. If they get fewer than that, they suffer a failure. The number is based on the number of players that are in the challenge.

Table 2. Successes needed for Victory
Players	Victory P. Victory Failure
2	4+	3	Less than 3
3	6+	4-5	Less than 4
4	7+	5-6	Less than 5
5	8+	6-7	Less than 6
6	10+	8-9	Less than 8
7	12+	10-11	Less than 10

Failure “Guys, we have a problem”: The party has failed to acquire the goals of the challenge and/or has suffered a significant setback in the process.
Partial Victory “Its not over yet”: The party has accomplished most of the goal, but there’s still more to be done, or there are loose ends to tie up.
Victory “A job well done”: The party has completed all of the goals of the challenge, and is ready for a new adventure.

Types of Challenges
Every Skill Challenge has a type chosen by the DM. The type determines what kinds of skills are generally appropriate to the challenge, as well as the consequences of success and failure. There are three possible kinds of challenges:

DM NOTE: The challenge types are designed to be a quick way for players to know what skills to use, and a guide for you to design the results of success and failures. However, never feel stifled by the challenge types; use them to your own benefit.​

A Mental challenge lets the players using their minds and their senses to gain clues and to find their way around the world. DMs can use Mental Challenges to describe large scales of scenery and give players a chance to work out clues to obtain victory.

Example: Finding your way through an old forest, determining the secret entrance to the underground city, solving the puzzle of El-Karad, or finding the last ingredient for a ritual in an old library are examples of a Mental Challenge.

Standard skills for a mental challenge include:
Arcana (Int)
Dungeoneering (Wis)
Heal (Wis)*
History (Int)
Insight (Wis)
Nature (Wis)
Perception (Wis)
Religion (Int)
Streetwise (Cha)^
*When dealing with anatomy or medical insights.
^For navigating urban terrain or gaining information on the street.​

Failure: Failing a mental challenge often means you arrive at a different location than the one you had intended, or that you obtain a piece of information…only to later find out it is incorrect.
Partial Victory: You gain some of the information you need, but need more. However, you know where to go to get more information. You successfully navigate the terrain, but are greatly delayed, or miss out on a special place as you make your way.
Victory: You gain the information you need and solve the puzzle. You navigate the terrain quickly and easily, and find a special location along the way.

A physical challenge often is the most versatile of challenges. It can include subtle stealth or outrageous stunts. Players are encouraged to describe their actions in detail.

Example: Scaling a great cliff, sneaking past a group of guards, and crossing a raging river are good physical challenges.

Standard skills for a Physical Challenge include:
Acrobatics (Dex)
Athletics (Str)
Endurance (Con)
Heal (Wis)
Stealth (Dex)
Thievery (Dex)
Social (cha)*
Knowledge (int or wis)^
*Social skills can sometimes be useful in physical challenges against other creatures. Using bluff to throw off a group of guards as you make your escape is a good example.
^Knowledge skills can sometimes be useful in physical challenges that involve certain environments. Using nature in a chase scene that involves the jungle is one example.​

Failure: Failing a physical challenge usually involves physical fatigue and possibly great peril. Examples include every party member losing two healing surges. Or each person in the party loses ¼ of their hit points, and then is forced into a combat.
Partial Victory: The party has overcome the obstacle but may have created new obstacles in the process. For example, the party has to climb a rock wall in a way that leads to other hazardous terrain. Or the party completes the task but suffers fatigue in the form of losing 2 healing surges each.
Victory: The party overcomes the obstacle, fresh, strong and ready for the next one.

A social challenge generally involves talking and a large amount of roleplaying. Players are encouraged to use eloquent words, bold statements, and outright lies to win the day.

Example: A negotiation with the Duke, talking your way past the guards, and convincing an old hero to take up the cause once again are examples of social challenges.

Standard Skills for a social challenge include:
Bluff (cha)
Insight (wis)
Intimidate (cha)
Streetwise (cha)
Knowledges * (int or wis)
*In some cases, some knowledge skills can be useful if they are particularly relevant to the challenge. Example: Using religion in a social challenge that involves a priest.​

Failure: Failing a social challenge normally means the party does not get their desired help, and often the other group’s opinion of the party has dropped. If the opposing group was already hostile, it may result in combat.
Partial Victory: Generally the party gets what they want, but the other group wants something too. Good examples are a rare treasure, some key information, or a favor. This can often led to another quest.
Victory: The party gets what they want. In many cases the other side will feel greater respect (or awe) for the party.

Same Scene, Different Skill Type.
One DMs social challenge is another ones physical challenge. Most environments could have any of the three challenges. The question you have to ask yourself is, “what is the main challenge my party is trying to overcome?”

Example: The party is traveling through a forest. What challenge type would that be. The answer is….it depends!!

Scenario 1: The Forest of Wonders (Mental)
The party is traveling through an ancient forest. The forest moves and often those that enter it are lost forever. The party must use their woodsman skills and their knowledges to figure out the clues of the forest, and ultimately the way out.

Scenario 2: The Treacherous Forest (Physical)
The party is traveling through a forest that is more like a jungle. The heat is intense, and the humidity large. Disease is rampant, and the trees are so thick at times the party must cut their way through. The party must endure the harsh conditions of the woods in order to make it to the other side.

Scenario 3: The Druids of the Forest (Social)
The party is in a mysterious wood and can’t find the way out. They find a group of druids that may have the answer. But the druids will need convincing, and the wrong word could spell doom for the party.

Awarding XP
For a basic skill challenge, give the party the same XP as you would if you were using a complexity 5 skill challenge in the standard system.

That’s it!
So that is everything you need to know to run the Obsidian Skill Challenge System. However, should you desire some more advanced options, including larger skill challenges and skill challenges during combat, check out the next post!


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Everything you need to run a basic skill challenge is given above. However, the system has a lot more options in store for DMs who would like them.

Optional Rules:
Roll before the Action: In some cases, the DM may desire the players to roll before they describe their actions during a skill challenge. This can be useful in social challenges, as the players can then “act out” the results of their checks.

Rolling Initiative: In the standard system, players are assumed to describe their actions in whatever order is appropriate and roll simultaneously. However, feel free to have the players roll initiative if it helps you run the challenge.

Total Victory and Total Defeat: In some challenges, a DM may not desire partial victory, instead wanting either complete victory or complete failure. In that case, remove the success number from the challenge, and just use the partial victory number. From there, feel free to change the DC to suit your desired difficulty.

Going for Broke: This rule gives players more control over their actions in a skill challenge, and allows them to come back from greater failure. During the third (and last) segment of a skill challenge, players can take a -5 to their skill rolls. If they still make the DC, they receive one additional success. So a players who gets a critical success would receive 3 successes. Players must choose whether to go for broke before any players have made their skill rolls. In general this will give the players fewer partial victories and more full successes.

Same Skill as long as a Different Description: Once the DM has decided to allow a skill, the system allows the player to use that skill over and over again for every segment of the skill challenge. However, if a DM wants to encourage more creativity, he can rule that a player can only use the same skill if he comes up with a new description for it, or continues to roleplay the skill appropriately.

Skill Challenges equal More Combat: In general, skill challenges provide an alternative to combat. However, in many cases combat is a big part of the fun for players, and while they are happy to win a challenge, they may also secretly have wished to fail if it provided a combat.

When using this option, place a combat at the end of your challenge regardless of whether the players succeed or fail. Instead, have failure provide them a -1 to their attack rolls in combat, partial victory give them an extra action point they can use (or an extra second wind perhaps) and a victory provide them a +1 to their attack rolls.

Larger Skill Challenges
Sometimes, one skill challenge isn’t enough! There are three general instances when a DM would like to have more than one skill challenge:
1) Partial Victory. By their nature, partial victories invoke unfinished work, which could mean another skill challenge for the party.

2) More in-depth challenges. The DM would like to use skill challenges as a large quest or an epic journey.

3) Mixed Challenges. A DM wants to use a wider range of skill challenges, including mental, physical, and social challenges all in one.

Building off a Partial Victory: Feel free to create another basic challenge for the party, and insert it later in the adventure to tie up the loose ends they left in the first challenge. In this case, you may want to use the “Total Victory and Total Defeat” optional rule listed above so that one way or another, the party will be done after the second challenge.

Building a larger challenge: This is very easy in the Obsidian system. Just follow these steps:
1) Choose a basic skill challenge, and give it a type.
2) If the party fails the challenge, don’t give them a standard penalty. Instead, they receive a -1 to all skill rolls involved in the next section of the challenge.
3) If the party gets a victory, don’t give them a standard bonus. Instead, they receive a +1 to all skill rolls involved in the next section of the challenge.
4) If the party gets a partial victory, they receive no additional bonus or penalty, and proceed to the next phase of the challenge.
5) Repeat steps 1-4 to add as many sections to the challenge as you like. Feel free to use different types as well.
6) For the final challenge, provide failure and success benefits as normal. You may wish to make these grander than normal, as the final result is the effort of many challenges.

Example Large Challenge: Escape from Jail.

Section 1 Breakout (Social Challenge)
The party is in a high security jail, but one of the guards is sympathetic to their cause. With enough persuasion, the guard might let them out.

Primary Skill: Diplomacy

Failure: The guard sets a trap for the party to teach them a lesson. The party is released, but many guards are waiting for them. They enter the next challenge with a -1 to all of their skill checks in the next section.
Partial Victory: The guard lets the party out, but only seconds before security is alerted. The party must proceed to the next section with no bonus or penalty.
Victory: The party enlists several guards to help, and manages to escape well before security is alerted. They receive a +1 to their skill checks for the next section.

Section 2: The Chase (Physical)
The party is on the run, being chased by the guards. They must make their way to the exit of the city and escape.

Primary Skill: Athletics, Endurance

Failure: The party manages to escape the city, but is terribly winded from the chase, and the guards are not far behind. They receive a -1 to all skill checks for the next section of the challenge.
Partial Victory: The party escapes the city, but the guards are not far behind. They proceed to the next section of the challenge.
Victory: The party is well ahead of the guards. They receive a +1 on their skill checks for the next section.

Final Section: Forest Walk (Mental)
The party must navigate the forest of Myar, which surrounds the city, with the guards on their heels and patrols in the woods. They must find the quick ways through the dense forest, or be overtaken by the patrols.

Primary Skill: Nature

Failure: The party is surrounded by guards and asked to surrender. The encounter is extremely difficult for the party, and may result in several deaths. The players can fight or surrender. If they surrender, they are taken to the city magistrate.
Partial Victory: The party escapes most of the patrols, but one lies between them and freedom. Set up a standard encounter for the party. If they succeed, the party is free, but tightened security will make it extremely difficult to enter the city again.
Victory: The party makes it by all of the patrols, and escapes without incident. In addition, they manage to find a dropped report that gives detailed information about the security of the city, which would assist if the party decides to return there later.

Skill Challenges in Combat
Sometimes, a DM would like to combine combat and skill challenges into a single encounter. The Obsidian System only needs a small tweak to make this happen.
Follow these steps:

1) Create a basic skill challenge, and assign it a type. Generally, combat skill challenges are physical or mental ones.
2) Each player can make one skill check for every move action they spend. So a player could make 2 skill checks in a round, or 3 if using an action point.
3) Decide failure, victory, and partial victory normally. In general, activate the effects of a partial victory when it happens, and then add in the effects of the full success if/when the party obtains it.
4) For XP purposes, treat the skill challenge as a complexity 3 if you were using the standard system.

Optional Rule: “No time limit”. In some cases, the DM doesn’t want failure in the challenge. The players’ use of actions is enough of a payment to overcome a challenge. In this case, don’t use the standard 3 segment rule. Let players continue to make checks as they desire until the overcome the challenge.

Example: The trap (Physical Challenge)
The party is facing a series of monsters and a metal disk trap that is a serious hazard. They must overcome the monsters but if they don’t disable the trap it will become even deadlier.

Primary Skill: Thievery

Failure: The trap ramps up, gaining +2 to its attack and damage rolls.
Partial Victory: The trap is weakened, taking a -2 to its attack and damage rolls (this occurs immediately whenever the party reaches the required number of successes).
Victory: The trap shuts down completely (this occurs immediately whenever the party reaches the required number of successes).
Using the “No Time Limit” Optional Rule: The trap does not ramp up. It continues to attack the party until the party gets the required number of successes to weaken or disable the trap, or until the party leaves the trap behind.

Adjusting the Difficulty of the System to your party.
The system assumes that for a 5 man party, against any challenge a party will have:

1) ONE good skill user, who has a high stat and training in a skill useful to the challenge.

2) TWO average skill users, who have training, but a lower stat (or an armor check penalty).

3) TWO poor users. These guys have no training and a weak stat in the skill.

With such a party, the system gives around a 30% failure rate, a 30% partial victory, and a 40% total victory rate for an equal level challenge (so 70% of the time the party is winning something)
DMs may wish to tweak the system to mold it better for their party. In general, adding +1 to the DC increases the challenge of the system by about 10%. Further, every +1 each party member gains to a skill increases the party’s win chances by about 2%. That means if a player gains a +5 to a skill (such as by skill training) then increasing the DC by 1 will balance out the challenge.

If a DM wants a different tweak, he can increase or decrease the victory number without touching the partial victory number. This will change the ratio between partial and total victory, but the party’s failure rate won’t change. Note that this effect is actually quite large, if you increase the number by 1, you decrease the total success rate by 16% (and increase the partial victory by the same amount).
IMPORTANT NOTE: The 3 segments are an important part of the system. Changing the number of segments in a skill challenge block will greatly change the system, and is not recommended.

So that’s it. You know have all the weapons in the Obsidian system. If you want even more information about the system, take a look at the next post.
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The Nuts and Bolts of the Obsidian System (Version 1.0)

This section is just detailing how and why the system does what it does. This is all COMPLETELY OPTIONAL INFORMATION! Please don't feel that you have to read this to understand the system.

Why the name Obsidian?
I would love to tell you all it represents the polishing of a rough system into something smooth and wonderful or something like that. But the honest answer is it popped in my head, and it sounded so cool to me I had to use it!

Changing the Paradigm, why did I choose to create Obsidian?
Unlike my other skill challenge system, Obsidian represents a very different way of thinking about a skill challenge. People may be wondering why I went this direction, especially considering how much time and effort (and snacks!) went into creating my other system.
The answer is NOT that I’m unhappy with my other system. I think it is a great step forward in the skill challenge progression, under the paradigm of success/failure complexities.

The answer is that as my group started playing skill challenges, several things came out that they disliked about it. It had nothing to do with my tweaks to the system, but more to the core mechanics of the system, which are as follows:

1) For most skill challenges, every player should get the opportunity to use one of his best skills.​

My group had several problems with this. First of all, we don’t like the idea that everyone is awesome at every moment. It goes to the quote from the “Inevitables” movie, “If everyone is special, no one is.” While we like the idea of every player participating in a skill challenge, we didn’t want every player to participate equally every time. The fighter should be great in physical time challenges and not so great in social ones. However, one of the benefits of 4e that we like is that because the skill discrepancy isn’t as large, while a fighter isn’t as good in a social scene as the rogue perhaps, the difference isn’t so large the fighter may as well not be there. He can still help, just not as much.

Further, we noticed that players trying to use their best skills started feeling “mechanical”. In 3e when we would do a “social challenge” the party would talk to the duke, we would roll a diplomacy check, and be done with it. In 4e the wizard is thinking how his arcana will work, the fighter is trying to think of some crazy thing to do with athletics, the cleric wants to talk about his god as if that will automatically help, while the rogue just sighs and rolls diplomacy. In the challenge, we wanted people to be roleplaying and rolling diplomacy, intimidate, and bluff checks. And if every character isn’t the best at that, that’s okay, the party should still have a good chance of winning the challenge.

2) A player’s effort can actually hurt the party. A failed roll can “ruin” the challenge for the group.​

In combat, generally the worst thing a player can do is do nothing. He misses with his attack, doesn’t take any hits, and just basically contributes nothing to that round of combat. However, in the standard skill challenge, you can do worse than that. Your rolls can actually hurt the party’s chances of success. In the worst case scenario (complexity 1 for example), two players can end the challenge before the other players even have a chance to go.

We noticed at our table that players didn’t like that. In some cases, the players would rather have not gone then rolled badly for the challenge. Aid Another is a fix for that, the problem is aid another is such a powerful mechanic mathematically that if you allow it freely the math gets screwed up. Don’t allow it, and the failure problem raises its head.
With these problems in mind, I set out to create a brand new system that would keep the core benefits of the skill challenge system (multiple rolls for success and failure, everyone participating) but could knock out these drawbacks.

No more complexities, the 3 Segment System
In doing work on my other skill challenge system, I learned something early on. Complexities are…complex! Mathematically when you start messing with complexities things get hairy very fast. This system is no different, and so I was prepared to delve into the depths of crazy math once again.

But wait I said! Does it have to be that way? One of the things my group wanted was “not everything should be a skill challenge”. Sometimes its okay for the party’s face to say a few words, roll a diplomacy check, and everyone goes on their way.
That led to the first structure of the Obsidian system:

OBSIDIAN POINT: A Skill Challenge should represent a significant encounter to the party. Quicker actions should be handled by single skill rolls.​

With this in mind, I tossed complexity 1 and 2 challenges as too fast for a skill challenge. So I begin work on fewer complexities. But then I thought back to Problem 2 listed above. There’s nothing less fun than a player not getting to go in an encounter, yet with the standard system this will happen from time to time. I did not want the same issue to happen in my system, and suddenly things started coming together:

OBSIDIAN POINT: Time with the DM is one of most important “fun currencies” a player has. While each player will not have equal success in every skill challenge, they should have equal time.​

I decided right then and there that complexities would go out the window. Instead, there would a single, solid system around everything was based. And so the 3 segment system was born. And it provides a load of advantages:

1) Consistency: When a DM calls for a skill challenge, every player knows what they are doing. They will describe their actions, roll 3 checks, and the DM will total it up and determine victory or failure. The DM has a core building block to work with, allowing him to focus more time on describing the challenge, and less on determining the mechanics.
2) Mathematically Elegant: Once I took out the complexity factor in the math, everything became much smoother. I no longer had to consider rules that would act differently at different complexities. Everything is tailored to the 3 segment system.
3) Easy to Scale: The core system provides a “building block”, one a DM can combine with multiple blocks to create as large a challenge as he wants. Further, the system is easy to scale to larger or smaller parties.
4) Equal Time: Every player receives the same number of rolls. While some players will naturally do better in certain challenges, every player gets the chance to describe his actions and see the results.

Player Options, Injecting a bit more Fun
My goal was to keep the game very simple to the players. They are to focus on the roleplaying, and let the system act as a backdrop. However, I wanted to give them a few things to do above and beyond just roll a die.

Primary Skill: If your researching ancient text in a library, athletics isn’t going to help you. Players are encouraged to use knowledge skills for such a challenge, and I wanted to provide an incentive for that. In addition, some skills are better than others for different challenges. For example, if players are sneaking in to an orc camp, athletics may be useful, but probably not as useful as being good in stealth. I wanted to highlight that.

So the Primary Skill concept was born: It gives players a carrot when the use the skills most appropriate for the challenge. And it ensures that if a player has no skill useful for the challenge, at least he will have a +2 to help him out.

Bold Recovery: This is a carryover from my other system. Players always enjoy the chance to redo their mistakes, and it give players a way to comeback when they do badly out of the gate. This mechanic has gone through many revisions, and in the Obsidian system it works with an action point. The reason is the action point is a core mechanic that already lets players go above and beyond. Further, its expendable, meaning players won’t just use them willy nilly. And lastly, because if I didn’t do it, someone else would.

Players are going to naturally ask if they can use action points to do something in a skill challenge. If I didn’t put an action point mechanic in the system, many Dms would just create something off the cuff. Good DMs can do that with ease, but I wanted the mechanic to be core so DMs know that a reroll with an action point is okay with this system. From there they can change it if they want.

Critical Success: This mechanic is hardly new, but it works well with the Obsidian system. The way the math works out, it provides a small yet noticeable bonus to the party. And no party will forget the time Skilly McAwesome rolls 3 natural 20’s in a row and wins the skill challenge.

Determine Skills Allowed, the Great DM Decision
In any skill challenge, probably the hardest (and most contested) decision a DM will make is what skills to allow for the challenge. After all, the skill the party uses is the heart of the challenge. Further, players naturally want to win, and so will want to use the best bonuses they can get their hands on.

This is the great schism between the standard system and the Obsidian system:

OBSIDIAN POINT: Not every skill works in every challenge. Players should focus on their actions, and not in picking skills. Use social skills for social challenges, physical ones for physical challenges, and mental/sensory skills for information challenges.​

I have repeated this point in the core mechanics as well. The reason is I want the DM to feel empowered to disallow skills with this system. Its not about knocking the players down, its about giving everyone a different chance to shine and getting the players past the mechanics and into the roleplaying.

Winning and Losing, the clock becomes the new villain.
Nothing will stop a player’s action faster than telling him he’s about to screw the party. Whether it’s a helpful nature or simply raw peer pressure, most people aren’t going to actively hurt the party with their actions (except you Kender people, you know who you are). However, in the standard system this happens. If the player isn’t using his best skill, he might get a failure (A BLACK MARK!) for the group. Correcting this was of primary importance.

OBSIDIAN POINT: The party should win and lose together. Each player should feel his rolls are contributing to the party’s success, and not in any way be a determent.​

Now, the reality is that failure IS a core part of the system, so the idea that individuals aren’t failing, it’s the group, is a bit of an illusion. Take a combat for example. Let’s say you have 5 players, but one player isn’t as good in combat as the others (harder to do in 4e then previous systems but still possible). The Dm throws 5 monsters at his 5 players. Next session the 5th player can’t make it, so the DM only uses 4 monsters. The party may actually do better without the 5th player.
The same happens in the Obsidian system, but it’s the perception of things that is important. The party is facing a skill challenge, and needs all the rolls it can get, whether it’s the smooth talking rogue or the bumbling fighter.

Further, in the standard system, the “enemy” of the party …. Is the party. The party can only lose when it rolls. That mentally encourages lack of action. In the Obsidian system, the “enemy” is now the clock, the 3 segments the players have to complete their challenge. Nothing brings a party together more than a common enemy. Every player will roll and hope for success, because in 3 segments they will have failed if they do nothing. This encourages players to be proactive, roll and win, don’t roll and fail.

Partial Victory: “Its not over yet.”
Keith Baker (who worked on the 3e Ebberon System) wrote an article about the standard skill challenge system. In it he mentioned one of the best ways to run the system was to include partial successes in the mix. I really took that point to heart.

OBSIDIAN POINT: Not all skill challenges are win/lose. Sometimes a party completes dominates a challenge, and other times they find they have more to do. A skill challenge system should encourage further adventuring.​

Partial Successes give DMs a nice hook to further adventures in their campaigns. If players do really well, they can pat themselves on the back and do something different. But in many cases, the reward is more adventuring.

Further, partial successes allow more gray areas for the DM to work with the party. It lets him say, “you guys did good, but not perfect”. Players can feel good that they accomplished something, yet still be hungry and hope that next time they can completely win a challenge.
Also, it gives DMs a way to tweak the difficulty of the challenge. A DM may not want the players to “fail” but he doesn’t want them to completely “win” either. Partial Successes allow the DM the middle ground.

Challenge Types: The Guidebook for Players and DMs alike.
One of the things my group greatly desired was a system that was a bit more invisible. The players should think less about the system and more on their actions.

Obsidian Point: A skill system should allow players and DMs to quickly figure out what they need to do, then forget about the mechanics and focus on the actions and roleplay of the challenge.​

I created the idea of Challenge Types to let the DM zero in on what kind of challenge he wanted to do, and then instantly communicate that to the players.

When a DM says, “This is a social challenge”, the players instantly know they should be thinking about making diplomatic gestures, intimidating looks, or clever bluffs. Conversely, if it’s a “physical challenge” the players put the words away and think about acrobatic stunts and stealthy maneuvers.

Further, it gives the DM some general boundaries on what skills are allowed. A players should expect most mental skills to be allowed in a mental challenge, but should except it when a DM says no to a nonmental skill.

The Straightjacket, the danger of challenge types. Obviously the danger of challenge types is players and Dms feel too restricted by them. Its important to note that this mechanic is a guidebook, it is not the ultimate authority of the Obsidian system. Dms should always have final say over what skills work for what challenges.
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First Post
Loved your work on the other thread. Will check back to see the full system/math!

What is the expected % win rate for a typical party?


First Post
So far I like it. Making the player side of the challenge very simple is a nice touch.

Am I right is saying that each player will get three rolls during the skill challenge?


To answer your questions:

1) What is the expected win rate of the party?

70-80%, which includes partial and total victories. In general, the partial victory rate is about 30%, and the total victory is 40%. That ratio changes slightly at different DCs, but that's a good approximation.

2) Does each player get 3 rolls every skill challenge?

Yes, every player always gets 3 rolls in a challenge.

Liking this a lot. Seems to allow for a wider variety of styles, e.g. time pressure vs none, total vs partial victory.

One simple suggestion for your Advanced Options: While I applaud moving a way from a successes vs. failures model and just requiring a threshold number of successes, I think it would make sense for certain failed rolls to actually count as a failure, by deducting from successes. Not standard failed rolls, but ones representing very risky attempts or counterproductive actions. For example, trying Intimidate on the King may be extremely risky; if you succeed on the roll it does help but if you fail it's worse than failing other checks; you really offend his majesty and you have a setback you need to make up for. If these cases are rare and usually clear or hinted at to the players they should be well aware of the risks so that it shouldn't come up unexpectedly or often so as to screw up your math.

Stalker0 said:
Yes, every player always gets 3 rolls in a challenge.
Funny thing; I wound up doing a skill challenge very similar to this as part of the final encounter wrapping up my 8 yr 3ed campaign, but I was just gut checking whether the skill checks were good enough because I had no good guidelines for DCs. It worked out fine but I would have loved to have the sort of guidance this will provide.

Fredrik Svanberg

First Post
This system is much better than the first one you did, in my opinion. Cleaner and easier to learn. Always using 3 rounds is a bit of a limitation to me but if it's necessary to make the math work I guess I can cope with that. I'm going to write down my own set of house rules for skill challenges now and I'll probably base much of them on this system.

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