Every combat needs a twist, something that makes it unique from every other encounter. Without some sort of combat modifier, your combat will largely become stale, regardless of the background you set it in. It can start to feel like your campaign's underground dungeons, sprawling fields, and populated cities are just differently colored backdrops for identical locations. In the best-case scenario your players will get too used to the routine of combat, and in the worst-case scenario, will yawn when you roll initiative and start wandering away from the table.
Your twists can take a lot of forms, but it's important that they be varied. Sometimes, you'll surround the party with enemies on all sides, other times there'll be spike traps all over the room or kobolds peeking out of murder-holes. Regardless of what you choose each time, your modifier should add another dimension to the battle, another thing for the players to wrap their minds around, in addition to their enemies. We'll get into more specific examples of combat twists soon, right after we cover some general types.
More often than not, your combat twists involve the arena in which the party and monsters battle it out. The easiest way switch up the environment is to change the geometry of the room, like employing narrow corridors or multiple levels. If you provide your players with exclusively circular and round rooms to fight in, you shouldn't be surprised when they get bored. And, of course, it goes without saying that you need to fill rooms with things, providing abundant cover and some areas of difficult terrain.
Moreover, features of the combat area should provide context and character to the space. If you want a battle in the city, you can have the enemies ducking in and out of buildings, running up staircases, and disappearing down back alleys. If you set a battle in the docks, a 10-foot wide pier over water can make a great limitation to the combat space. And if you set a battle in a dungeon, you can get really creative: swinging pendulums, hidden traps built into the floor and walls, spike traps, and lowering portcullises.
Combat twists that raise the stakes give the players another way to lose, in addition to simply dying. With all the focus on telling an epic story, you shouldn't be afraid to let your players lose every once in a while. If they are chasing a bad guy, he can get away; if they're going after an artifact, it can be destroyed mid-combat. Even if you make the stakes clear, your players won't take them seriously unless they actually fail once in a while, and this can provide a great way to spice up combat.
You can also put something new on the line, like innocent bystanders or a chest of treasure. Bonus points if the party has to fight the clock to save a person, place, or thing from utter peril. As long as the players can be persuaded to care about whatever you put on the line, you can change the entire focus of combat from 'kill the monster' to 'protect X from the monster' or even 'kill monster in a special way to get X.'
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d12 City Combat Twists
- The area is filled with innocent bystanders who are threatened by errant AoEs or projectiles. Enemies may take them as hostages, if appropriate.
- Enemies are trying to escape with or destroy something valuable.
- Area catches fire mid-combat and proceeds to erupt in a blaze. Flaming areas grow once a round.
- Combat becomes a chase scene down crowded city streets when the enemies try to flee.
- Combat takes place in a sewer. Random inflow pipes activate each round, drenching the square nearest to it.
- The party is ambushed in a very narrow alleyway, bridge, or pier.
- Snipers take shots at the party from a high balcony or window during the fight. They can be defeated, or merely avoided.
- The Town Guard interrupts the battle, and must be convinced of the party's innocence, or they will attempt to arrest the party along with the enemies.
- This area is filled with crates, coffins, or barrels stacked high, almost to the ceiling. They can be pushed over and used for cover. If appropriate, more enemies hide inside.
- One or more of the enemies has a large bounty if taken alive or has valuable information. Care must be taken to capture, rather than kill.
- The battle goes the rooftops. Enemies jump from roof to roof and a single misstep can mean a deadly fall.
- This room is filled with gunpowder or oil. The wrong attack means disaster.
d12 Dungeon Combat Twists
- Spike traps, pit traps, landmines, or caltrops litter some squares, threatening movement.
- Every other square is a column or pillar, providing easy cover, but also cutting visibility.
- The chamber is filling with a rising tide of water or sand.
- A portcullis suddenly falls, trapping half the party on opposite sides of a chamber just before enemies strike.
- This room is rigged with time-delay spear traps mounted to the ceiling. Spears strike the squares in which players begins their last turn.
- A very thick stone wall is slowly closing in front of a treasure chest. The party will have to work fast to retrieve it (or some of its contents) before the partition closes for good, all while battling the chamber's defenders.
- Spear traps on the ceiling fire on a delayed timer, striking where creatures began their last turn.
- The lighting in this chamber is magical, activating or deactivating once a round, flooding the room with darkness or light.
- This chamber is filled with raising platforms, lowering platforms, and conveyor belts. Once a round, party members are pushed about and elevations change.
- The room is full of statues, and enemies that look like statues.
- A number of aging pillars support the ceiling of this room. Damaging the majority of them brings the roof down.
- There's a bomb. The area will explode in 1 minute.
d12 Wilds Combat Twists
- An enemy will summon nearby reinforcements if not stopped.
- The party's means of transportation (horses, wagon, etc) are threatened by combat.
- The party is ambushed on a long, rickety rope bridge over a deep chasm.
- Tall grasses conceal bear traps that spring on unwary adventurers.
- The enemies have the high ground. The party must fight their way up a steep, winding path to the top of the hill or tower.
- Thick fog, rain, or snow covers the area. Archers are useless here, and visibility is very low.
- Sharp stones, broken glass, or caltrops threaten to slice the feet for any creature that moves.
- The forest's trees, vines, and bushes have a life of their own. Once a round, they move, blocking line of sight or entangling players.
- Wandering monsters appear in the black of the night. Players without darkvision or magic must light a torch before they can see.
- A wagon full of treasure and equipment rolls away from the party, gaining speed and momentum, heading towards a cliff.
- The battle takes place on a sinking ship. Treasure can be found on the ship before it sinks, but, more importantly, the party needs to find a safe lifeboat.
- Much of the area is quicksand, which is difficult terrain. Every 5 feet a player moves, they sink 1 foot deeper.