Mike Mearls, former D&D 5e designer, has shared data outlining why the system's biggest fights often disappoint players. "If you run D&D 5e, you might find that your boss monsters die easily", he says in a Bluesky post from October 8. According to Mearls, the problem lies with the fact that players are facing too few fights between long rests.
Mearls, who worked on D&D between 2005 and 2023, says, "The game was built around the assumption that characters would engage in about 20 rounds of combat between long rests". Given that fifth edition's fights are expected to last three to four rounds, that's five or six combat encounters per day.
Anyone who's played a DnD campaign lately knows that this many fights between rests is uncommon unless your DM is running a particularly grueling gauntlet. In games that have a heavy focus on exploration or social intrigue, you might see closer to one or two combat encounters before the party turns in for the night.
The main problem this causes (according to Mearls, at least) is that players can more liberally use their most powerful abilities. "In 4e, we assumed a certain number of encounters per day", he explains. "In each encounter, we assumed you used encounter powers, then at-will. We spread out the extra damage from daily powers across the day."
"We did the same thing in 5e, and time has shown that it does not work for boss monsters", he continues. "Why? The gap between daily and at-will damage is far bigger in 5e than in 4e. Spreading that extra damage across every round of a day misses the real benefit of daily abilities - a massive damage spike."
Mearls backs his claims up with a graph comparing the possible damage of a Battle Master Fighter 5e. One line shows the damage the character can deal with abilities they have access to at all times, while the other shows their maximum damage potential when using their more powerful, limited-use abilities.
"A party that unloads with their best powers simply breaks the system", Mearls says. "Their output is off the scale when you assume that everyone fights for 20+ rounds per day and spreads their at-will powers out." "It's quite likely that a semi-optimized party can vaporize boss monsters in a round or even less."
Based on my experiences running D&D, Mearl's assertions are sound. What they don't acknowledge is that the long rest problem is something of a self-inflicted wound. Back when D&D 5e was being playtested, its early designs openly said that the recommended number of encounters between long rests was four - or as few as two if you throw some particularly challenging fights in there.
This would have been ensured by dramatically decreasing the power of player-characters. Take the Wizard 5e, for example. In 5e's fourth playtest, a level-10 Wizard had 10 spell slots: two slots each for spell levels one through five. The published 2014 class had 15 spell slots: four level-one slots, three for levels two to four, and two for level five.
As the playtests developed, the power of the DnD classes grew. Naturally, this led to a Dungeon Master's Guide that recommended "six to eight medium or hard encounters in a day". That's an absolute grindfest that suits a Temple of Elemental Evil campaign just fine, but it's one that's become increasingly outmoded. Filler fights quickly grow dull for a party, as it's often obvious which encounters matter and which are purely there to drain your resources. Plus, in the age of actual plays, many have begun to prioritize narrative over endless strategic combat sessions.
Mearl's suggested solution is "to design boss monsters with a different hit point scale, one that assumes the party is alpha striking". He acknowledges that this breaks fifth edition's Challenge Rating system (something Mearls himself had a hand in designing), "but I think it's a viable path to introducing boss monsters that can stick around".
Sadly for boss monsters, Wizards of the Coast isn't likely to implement any major design changes soon. The dust has only just begun to settle on the 2024 rules overhaul. If boss fights are getting a makeover, it'll be a gradual process, one that doesn't require a complete overhaul of how players and monsters work.
Got your own opinions on how 5e handles boss fights? Tell us in the Wargamer Discord. Or, for more rules, here's all you need to know about DnD races and DnD backgrounds.