In the 5e.2014 rules, high level monks will also vex you DMing a high level game because of the way they can spam stunning strikes. Most monsters, even high level ones, aren't immune to being stunned. While it's a great way to peel off legendary resistance, it is otherwise pretty frustrating since it cripples the NPC/monster action economy vs the PC action economy. Constitution saves tend to be pretty good, but you will see loads of your monsters, even high level ones, stunned frequently.
Fortunately, this is improved at least a bit in the 5e.2024 rules since the monk can only attempt it once per turn.
During 3.x and Pathfinder 1st, I hated how powerful PC's could become especially towards the higher end. The D20 system did break at those levels. What I have realised, coming back to D&D with 2024, is that the system feels more balanced than it ever did before. Scaling works about right. In one of my two campaigns, there is a Goliath Monk 8/Ranger 1. His shtick is Hunter's Mark, knock the enemy prone, and beat the snot out of it with advantage. At first I was like, my gods, is this broken! But then I realised how much the player enjoyed showing off what he could do and he's no power gaming. I let the party cook and do their thing without worrying, and how that has made the campaign on both sides of the screen that much more enjoyable. They have abilities so let them use them. Let them be the heroes of legend.
One thing I learned on these forums was, if a BBEG fight was going too easy, don't up the HP of the baddie, just boost the damage that he does. The characters take more damage, forcing them too use resources or change tactics, and they still get to feel like powerful heroes when they take something down.
CR is a guideline. Always has been. 2024 encounter generator seems to work well but look at what your characters have access to and you can plan a higher CR encounter to challenge but not kill them. In the campaign I mentioned above, the party were 8th level going into The Styes adventure from Ghosts of Saltmarsh. They took on the
juvenile Kraken which is CR 14
with the loss of the party wizard who was revived after the fight. They were capable of handling it because I kept abreast of and knew what their capabilities were.
Another thing that I have done in higher level games in the past, is to remember that not every session/adventure has to be a fight. You can have roleplay sessions, intrigue and the like, with kingdoms, celestials/fiends/archfey, and so forth that don't need combat.
During 3.x and Pathfinder 1st, I hated how powerful PC's could become especially towards the higher end. The D20 system did break at those levels. What I have realised, coming back to D&D with 2024, is that the system feels more balanced than it ever did before. Scaling works about right. In one of my two campaigns, there is a Goliath Monk 8/Ranger 1. His shtick is Hunter's Mark, knock the enemy prone, and beat the snot out of it with advantage. At first I was like, my gods, is this broken! But then I realised how much the player enjoyed showing off what he could do and he's no power gaming. I let the party cook and do their thing without worrying, and how that has made the campaign on both sides of the screen that much more enjoyable. They have abilities so let them use them. Let them be the heroes of legend.
One thing I learned on these forums was, if a BBEG fight was going too easy, don't up the HP of the baddie, just boost the damage that he does. The characters take more damage, forcing them too use resources or change tactics, and they still get to feel like powerful heroes when they take something down.
CR is a guideline. Always has been. 2024 encounter generator seems to work well but look at what your characters have access to and you can plan a higher CR encounter to challenge but not kill them. In the campaign I mentioned above, the party were 8th level going into The Styes adventure from Ghosts of Saltmarsh. They took on the
juvenile Kraken which is CR 14
with the loss of the party wizard who was revived after the fight. They were capable of handling it because I kept abreast of and knew what their capabilities were.
Another thing that I have done in higher level games in the past, is to remember that not every session/adventure has to be a fight. You can have roleplay sessions, intrigue and the like, with kingdoms, celestials/fiends/archfey, and so forth that don't need combat.
Another thing that I have done in higher level games in the past, is to remember that not every session/adventure has to be a fight. You can have roleplay sessions, intrigue and the like, with kingdoms, celestials/fiends/archfey, and so forth that don't need combat.
I am partial to the fey because it doesn't evoke quite the same "end of the world" threat that demons and devils seem to, and yet fey can still traumatize a geographic region.
So the PCs could nuke sprites and pixies and such, but that may bring fey knights. Courts of the Shadowfey has some good mechanisms for PCs to fight duels, win drinking contests, hunt creatures, etc to gain standing rather than rely on outright violence.
High AC characters with a cloak of displacement suck. Fighters with high end magic armor, magic shields, and cloaks of displacement will annoy you. High AC is hard enough to hit without disadvantage in doing so - so you'll have to constantly work hard to strip that disadvantage from them to even that fight out a bit.
In general, PCs can accumulate some pretty substantial defensive gear over their levels. And that's good... to a point. There's a good reason defensive magic in the form of magic armor got a lot rarer in 5e than other editions. I think most people tend to worry about PCs having too much offense, but they can be unbalanced with defense as well.
A note on Cloaks of Displacement - they can be taken out of the picture by attacks against saves (such as area effect spells like Fireball, Web or spells that entangle) or the likes of Magic Missile, that allies of the attacker can then use to their advantage - until the player's next turn.
The big thing is, don't rely on one way to attack characters - AC, saves or whatnot. Always assume whatever you throw at characters, at least one PC will have a good defense against it. Hit them from all directions and ways to spread the hurt and the method of injury. Though players should see an advantage if they make defense a priority, it shouldn't become a cure-all to prevent adversity.
Sometimes the best way to challenge players is to find ways to not let them solve things with violence or whatever their Standard Operating Procedure is - high AC doesn't help you, for example, when you fall in a pit or are dodging a Fireball. Throw occasional curveballs at them - at least once per adventure if you can. Don't be afraid to stack or combine effects (such as the above mentioned pit in the area of a Antimagic Shell) to throw PCs off-balance - someone will have a feature that will get a chance to shine (such as the Monk's Slow Fall ability in the prior example).
I've run a 5E campaign from 1st to 20th level with 7 epic boons. Basically, 27th level. It lasted 122 sessions and had 5 player characters.
I have also run two campaigns from 1st to 13th level. Both had 3 player characters.
There's a few things I learned.
First, the game works really well with 3 PCs at any level. They feel heroic but always at risk. With 5 PCs they come on strong at level 5 and it just gets worse from there. It takes a lot of work to challenge them. So action economy matters a lot in 5E.
Second, to challenge a larger group of players, I set a minimum threshold for monster damage and accuracy by tier. Minimum to hit bonuses are +3, +6, +9, +12. For damage I take the average damage roll and multiply it by tier -- so 2x, 3x, and 4x. This allows me to throw a horde of goblin minions at Tier 2 characters, or ogres at Tier 3 characters, and still have them be effective. I also use a variety of legendary actions that "break the rules" -- Legendary Damage, Legendary Accuracy, Legendary Resistances, Legendary Saving Throws, etc. They all basically do what you expect they would do.
Third, my sense of immersion starts to break at about 13th level due to 7th level spells. They just take the game in a more fantastical direction. For future campaigns, I'll be curating the spell list to ensure the PCs don't start plane hopping if the campaign is about the survival of Shadowdale.
Fourth is related to third. Reskinning monsters allows me to tell a wider variety of stories at high level. For example, I found the Pit Fiend stat block to be very effective. But it can also be reskinned as an evil king, for example, if I want to keep the campaign more grounded and less planar.
Fifth and most importantly...campaign pacing. No one talks about this, but it's hugely important. In my experience, Tier 1 goes by in about a dozen sessions. So does Tier 4! A high level campaign needs to be paced with the assumption that high level play will come to a quick end. It's not something meant to be drawn out. It's concise, decisive, and epic. It's...well, it's the climax. Even if high level play is extra work for the DM...the good news is that it won't last forever. Make the most of it.
A lot of my High Level Play Rules are used at all levels 1-20.
Character Death. The Big One as always. Character death is amazing at making high level play and the game work.
No Buddy DM. Don't be "on the side of the players or characters". Be neutral.
DM Aggression. When playing a monster or a foe, they should quite often act to kill the characters.
No Questions. In general player can not ask OOC questions during my games. This keeps the game flowing fast.
Act, don't Ask. I hate this so much, when a player asks an annoying "can my character do or try X". In my game players simply act without asking tons of questions (see above).
No Free Knowledge. My games have no "roll to have the DM tell you stuff".
Lots of Homebrew. If you want to encounter only the exact things from the rulesbooks, I'm not the right DM for you. I like to keep things interesting.
The Three Second Rule. When any adventure worthy action starts a player has three seconds to state an action. One second more and the character stands confused for the whole round.
I saw the high speed tier 4, but think in our case it was the adventure path. We were doing
an up-leveled Ghosts of Salt Marsh and the "elemental lords"
were good for a level each. The fights were rough but the issue is the plot makes them literally one right after the other. It was far from the 5MWD but typically after lunch we were falling back a bit to recover, identify loot, level up and make our plan for the next morning's assault.
High AC characters with a cloak of displacement suck. Fighters with high end magic armor, magic shields, and cloaks of displacement will annoy you. High AC is hard enough to hit without disadvantage in doing so - so you'll have to constantly work hard to strip that disadvantage from them to even that fight out a bit.
In general, PCs can accumulate some pretty substantial defensive gear over their levels. And that's good... to a point. There's a good reason defensive magic in the form of magic armor got a lot rarer in 5e than other editions. I think most people tend to worry about PCs having too much offense, but they can be unbalanced with defense as well.
reworked +X weapons to +Xd6 damage only
+X armor is 2X reduction of all damage
Cloak/ring or protection gives 1/2/3/4 saving throw proficiency, depending on rarity.
+X shields do not exist, only +1 that requires attunement.
Related: In my Baldur's Gate II game, HP growth followed the 2e model. After level 10 you get 3, 2, or 1 hp per level based on your character class. Nobody's ever going to crack 200hp without an epic boon, and the casters are still a little under 100hp at level 17. This keeps the players from getting arrogant and just tanking multiple fireballs. The cleric was actually pretty happy to have a chance to pick up Absorb Elements (although it still wasn't enough to keep him from being basically one-shotted by Meteor Swarm when they ran into a serious spellcaster).
Unfortunately, at least on this axis, you're running into fully intentional aspects of the game design, that we were told about extensively during the "D&D Next" playtest.
They straight-up explicitly told us they were going to replace AC/hit scaling with greater HP/damage scaling instead. Like...that was very literally one of the intended selling points of D&D. Your HP will inflate to reflect your higher power level, because we're intentionally removing the scaling from all other areas of the game. That's one of the most deeply baked-in characteristics 5e has. You're...kinda going to have to just accept that.
Enemies can get higher to-hits than PCs, and often have easier access to Pack Tactics.
Notice we're seeing complaints about "fighters too hard to kill" and "fighters doing too much damage" here? 5e's higher levels are much more balanced than 3.5's were.
The sorcerer in my BG2 game is achieving some of his best damage by acting like a fighter (polymorph to giant crocodile, or Bhaal slayer form; literally defeated the BBEG one time by transforming and then tackling them both off a treetop to take 20d6 falling damage; Feather Fall doesn't help when you're being carried down by a 1500lb avatar of murder that's also trying to bite you for 3d12+x damage during the fall).
Of course 5e's levels are much more balanced than 3e's were. That's like saying that Death Valley is at a higher elevation than the Mariana Trench. That is true--indeed, it is a dramatically higher elevation!--but both are still below sea level. Being better than literally the least balanced version of D&D ever created is not a high bar; it's not even a low bar. Somehow digging deep enough to slip below that bar would be a difficult feat.
