The way combat plays out in D&D depends on a large number of factors, with the foes you choose to have face off against the characters usually chief among them. But the most memorable fights in the game are often the ones where the focus shifts beyond monsters and villains and the process of bashing away at them. Unexpected events, creatures doing things they don’t normally do, unusual environmental effects, and more can all inspire the players to engage with the fight on a level beyond baseline attack rolls and damage. Thankfully, there are plenty of easy ways to encourage that engagement for players and characters alike, including any of the following.
Talking Things Out
One of the most straightforward ways to shake up a combat encounter for most groups is to drop a social encounter into the middle of it. Have characters notice foes who look as if their hearts aren’t really in the fight — junior bandits, conscript cultists, monsters who realize the characters have them hopelessly outclassed, and so forth — and give them the opportunity to persuade or intimidate those foes into standing down. Successful roleplaying or skill checks can help thin the enemy ranks, but might also inspire those foes who are left to fight with renewed fury as they try to keep their side’s morale up.
Playing Against Type
Combats in the game often play out against a sense of how relatively tough each foe in the fight is and what kinds of damage and effects they dish out. As such, any minor adjustment to the foes’ baseline combat stats can easily freshen up a fight, especially for experienced players who know what monsters do. Changing up damage types is a dead easy tweak to make, with corrupt cultists dealing necrotic damage with their weapon attacks, monsters in an elemental shrine dealing acid, cold, or fire damage, and so forth. You can also add an extra 1d4 or 1d6 damage of a new type to just about any creature without messing up the difficulty of an encounter.
You can also make matched changes to any monster’s baseline stats to mix things up, pairing up a benefit and a detriment for balance. An easy example is lowering a monster’s AC to make them easier to hit, while giving them enough extra hit points to keep them in the fight for an extra round. Or in a group of identical monsters, let one attack with advantage even as you cut their hit points by half, creating a front-line foe whose combat prowess will freak the characters out, and whose early demise will feel like a huge win.
Turning the Tables
One of the best ways to make a combat encounter memorable for all the wrong reasons is to have a fight suddenly go way harder or way easier than you expected. One way to narratively adjust the threat level on the fly is to introduce some element during the fight — a conveniently spotted relic that a character grabs up, a suddenly active magical effect, a mysterious sound heard in the distance — that gets all the foes’ attention. Then have that element drive foes into a fighting frenzy with short-term bonuses or advantage on attack rolls to turn the heat up in a fight, or have it inspire a number of foes to flee if the combat is going unexpectedly hard. When the fight is done, you don’t even need to figure out why the chosen element has this effect on the party’s enemies. Instead, let the players speculate, then quietly adopt their most interesting idea.
Going to Ground
A static battlefield too easily lends itself to characters and foes not moving. So at the end of the first round of combat, have that battlefield go wonky. If the setting is a magical shrine, maybe that magic starts going haywire to turn stone to mud, to make the floor buckle, to cause creatures to spontaneously levitate against their will, and so forth. Out of doors, constant rain can fuel sudden ground-slips or sinkholes, or errant fire damage can set dry grass or trees alight to create quickly shifting areas of flame. Any ground-based effect that deals minor damage or imposes a short-term condition can help keep combatants in motion.
Where’d They Go?
Elements of the battlefield that hinder the perception of characters or their foes work especially well to keep ranged attackers and spellcasters from holing up at a safe location and strafing the other side. Shifting fog can be an easy addition to an outdoor encounter, while magical darkness might crop up around any old shrine or magical pool, or as a magical trap ready to be accidentally tripped during the fight. Keep areas of concealment moving whenever possible so combatants can’t just lock down alongside them. Or for an even higher-magic approach to the same end, have shifting pockets of teleportation magic scattered around an ancient ruin or wizard’s sanctum randomly fling characters into new locations, forcing them to move to regain optimal attack position.
Blast From the Past
Fighting in ancient ruins is a mainstay of the game, so don’t be afraid to let those ruins come back to life for a bit. When magic is unleashed or a character or monster crashes into a rusting lever, let the battlefield get nostalgic for what it once was. Have a dormant magical shrine come back to life, dealing damage or granting benefits to creatures who start their turns within a certain distance of it. Let an old fountain start spewing muddy water, whether laced with magic or simply making the floor around it dangerously slippery. Or have spectral threats manifest in response to being disturbed, whether as additional undead foes or deleterious environmental effects.