D&D 5E Challenging High-Level 5e Characters

[SlyFlourish]

As happens in my campaigns, the characters in my 12th level Empire of the Ghouls campaign have hit the point where they're able to mitigate a lot of the threat of big battles.

With ten years of D&D 5e behind us – what are your best approaches for keeping up challenging combat encounters for high level characters that don't take two to three hours to run?

What are your favorite tricks that keep the threat high but don't take agency away from the characters or the choices the players made in building them?

 

[UngainlyTitan]

Layered defences and reinforcements of mooks and some higher-level support before and around the boss in boss fights. Otherwise, I did not sweat it too much.
Increase the common monster numbers in other fights and make them some of them at least hard or deadly but for the most allow the party cruise through them. They have earned it by getting to that level.
I mostly use pre published material and for the most part I have only changed boss fights for high level parties. That said lately I have taken to run the party a level below the recommended level. it seems to work.
One other thing I have done in dungeon situations where it makes sense is have the nearby monster reinforce a triggered encounter. I have found the party can manage it and it makes sense. That the monsters would investigate the fight down the corridor and not just wait in their room to be picked off in detail.
Another thing, is if the dungeon is all of a faction and the party kills the leadership and a large proportion of the faction and withdraw to long rest. Then the rest flee the dungeon. For the Princes of the Apocalypse campaign for instance, in the various temples the party retreated after taking out the leadership and I had the rest flee.
I use milestone levelling.

 

[MerricB]

Two waves of enemies. And have the first wave weak enough so they perish to the nova strike of the players without taking too long.

Big Melee Monsters (with ranged options). Having a +10 or better to hit with a hefty damage behind it means the monsters' attacks feel meaningful. (There's nothing more frustrating than having Every Attack Miss as the DM.) You don't want to overwhelm the PCs or hit them too often, but monsters never hitting doesn't lead to excitement.

Targeted immunities and vulnerabilities. It's very easy for spellcasters to get into a rut. "I cast fireball". So immunity to fire (or weapons, etc.) means that characters must turn to other options. But don't make EVERY monster in every encounter immune to fire. Change things up. And making them vulnerable to things means the players are rewarded when they do figure out the trick. (If you run combats fast enough, it's okay for a player to be less effective in one combat when they're more effective in the next one).

I'm also fond of "reflect spells" properties on monsters, but with ways for players to overcome them. Sometimes it was spend a bonus action to make an Arcana check to find the "down time" when reflect wouldn't work - which I allowed after the first reflect spell happened. Or there are ways to overcome them.

Cheers,
Merric

 

[kigmatzomat]

Waves as other people have noted are good. I also suggest foes that are willing to flee to become recurring foes. If they can fall back into trees that block line of sight and give cover or head down a cave with a dead fall or a collapsible bridge you get several things.

First, smarter foes are frustrating but also in their own way fun. Second, the party may split up, or at least separate, which can allow more flanking or even the classic parthian shot. Third, it will likely burn some spell slots either on non-damaging mobility, by causing 1-minute spells to expire, or so AoE spells hit fewer targets.

One good option is a spellcaster that doesn't personally fight. They cast "improved invis" on a rogue and then flees (possibly Misty step) to get reinforcements. Use a Summon or maybe Animate Objects to have rocks mob the party caster. They fall back again, using fog cloud to break LoS (or to hide the Objects, which have blindsight). Maybe an illusion to hide a pit or make it seem like there's a bridge where there isn't. Perhaps they cast Thunderwave just as a way to draw attention (audible for 300ft) (or maybe it sends flasks of oils hurtling towards the party so a minion can throw a torch to light them up).

 

[DrJawaPhD]

What are your favorite tricks that keep the threat high but don't take agency away from the characters or the choices the players made in building them?

I give all "boss" type monsters complete immunity to all crowd control spells/abilities (and tell the players beforehand so there is no guesswork and frustration on their end). It's not that hard to balance fights if you know your BBEG will actually get to use its actions and legendary actions without being chain stunned / polymorphed / banished. Damage is pretty easy to estimate and keep balanced, it's the variables around how high level spells subvert the action economy that make balancing fights so difficult.

 

[Quickleaf]

Defenses that mitigate, but don't obviate.
Defenses that accelerate/intensify, rather than decelerate the pace/tension.

I'll explain: Years ago, I traced what I believe is one of the roots of 5e's Legendary Monsters to a 1995 AD&D Planescape monster book in which "Monster of Legend" (e.g. The Nemean Lion). The suggestions include several from Greek myth which require lateral thinking from the PCs. However there are two examples that are relevant to my 2 points:

Blood so corrosive or poisonous that any edged weapon damaging the creature must survive an item saving throw versus acid or be destroyed: Blood splashed on a hero fighting the monster might force a saving throw versus poison to avoid death! Or, optionally, drops of blood spilled on the ground might turn into scorpions, snakes, or some other complication.

A coat of shining scales that reflects any magical attack onto its caster, or that blinds any hero who gazes on the creature.

Other examples would be things like the monster delaying a condition/banishment for one round at the cost of Hit Points... or down-tuning Stunned to "can only make one attack on its turn & cannot make Reactions" or "can only make one attack on its turn & loses one Legendary Action that round." These get more interesting / effective if combined with something spicy like a damaging aura that activates.

 

[lolsworth]

Most combat encounters just won't be challenging, especially if you don't want them to take a long time. Player characters have so many options, and both monsters and player characters have so much hp that combat simply does take time at high levels.

Letting the players crush some encounters and feel great can be good towards the end of the campaign, leading into the big finale. And I think Empire of Ghouls ends around level 13.

Then for the finale:
Big armies of mooks to spend high level aoe spell slots on are my go to.
Minions that heal and cast restoration or buffs on the big bad are good as well. They help split the focus so its not just group up and attack the big bad
I've considered but not experimented with enemies that steal spell slots, or inflict exhaustion (-1 exhaustion, not normal exhaustion).

 

[Distracted DM]

Playing RAW using only WotC stuff, it's pretty hard. Frankly it's pretty hard to do

I give all "boss" type monsters complete immunity to all crowd control spells/abilities (and tell the players beforehand so there is no guesswork and frustration on their end). It's not that hard to balance fights if you know your BBEG will actually get to use its actions and legendary actions without being chain stunned / polymorphed / banished. Damage is pretty easy to estimate and keep balanced, it's the variables around how high level spells subvert the action economy that make balancing fights so difficult.

Yeah, it's pretty hard to challenge high level parties RAW, especially using only WotC resources. I never considered just... ignoring all CC abilities. I don't imagine my players would enjoy it.
Even 3 legendary resistances aren't much- they basically extend the fight by one round.

As happens in my campaigns, the characters in my 12th level Empire of the Ghouls campaign have hit the point where they're able to mitigate a lot of the threat of big battles.

With ten years of D&D 5e behind us – what are your best approaches for keeping up challenging combat encounters for high level characters that don't take two to three hours to run?

What are your favorite tricks that keep the threat high but don't take agency away from the characters or the choices the players made in building them?

OK so let's see what's regularly recommended:

The issue with using "lots of enemies" ends up being slog. Great- I can include a lot of enemies to challenge them, but it's going to make this high level fight take an entire session, and it wasn't even an incredibly meaningful fight.
OK, so only have meaningful fights... at high level..... so that means that you're going to be looking at 1 fight/day. So they party can really go full-tilt and alpha strike it.

I mostly run a5e now, which is great- I love the monsters and the balanced spells, feats, etc. except a5e gives martials the ability to stun (stunning assault maneuver), or blind for the combat without a save (berserker crit).

The best answer I can give is "use multiple big threats at once." At least that way your fight won't be super bogged down with lots of minions, and the party has to decide who they're going to focus on first.
But not taking 2 to 3 hours to run? At high levels? AND challenging the party? ... Nope. I got nothin'.

 

[Tonguez]

Dont have them fight the monster, have them fight the region and the lair actions.

Remember Aboleths can project its image and use their telepathy up to a mile away from its lair, dragons can be seen over miles away too, Reds cause earthquakes within 6 miles of their lairr and form portals to the Elemental Plane of Fire within 1 mile. Use that to start the waves of minions far from the monsters location, the powerful monster should be fully aware of the PCs coming and use the entire mile circumference of its ‘lair’ to defend its territory

 

[DrJawaPhD]

Yeah, it's pretty hard to challenge high level parties RAW, especially using only WotC resources. I never considered just... ignoring all CC abilities. I don't imagine my players would enjoy it.
Even 3 legendary resistances aren't much- they basically extend the fight by one round.

I've never had an issue with it, most players greatly prefer it once they are used to it. It's way better to be told up front that your gamebreaking spell just doesn't work on the BBEG than to engage in the frustrating loop of legendary resistances where your turns are straight up wasted until you burn through enough wasted turns to auto-win the fight. Also this change does wonders for narrowing the Martial vs Caster divide and letting all players at the table feel like they actually matter.

I'm not talking about banning CC entirely, just on the epic boss monster at the end of a story arc, stuff like that. Often times I'll also have some powerful minions with the boss that aren't immune, so CC spells still have their place in making the fight much easier without entirely trivializing it. Basically I just treat big fights like a World of Warcraft raid boss - makes it much easier to balance and ensure the fight is challenging enough to be satisfying when the players win