This encounter is meant to turn a relatively straightforward fantasy combat (a fight with a wizard and her goons) into something a little more challenging and dynamic through the use of mundane terrain. Lure the PCs into a barn, then trap them inside with opponents who are ready to make good use of the environment.
The encounter takes advantage of a not-uncommon feature in old barns: a mezzanine-style hayloft. Here, the hayloft (a second story for the storage of hay) doesn’t overhang the whole of the ground floor. In the case of this barn, it forms a ‘U’ shape, leaving the center of the barn uncovered. See below – the photo was taken from the ‘bottom’ of the ‘U’. Add to the below layout a pair of ladders to the hayloft beside the door, one on each side.
What sorts of enemies work well in this barn? Put the wizard in the hayloft at the base of the ‘U’. It’s a good position for firing down on the rest of the barn, and it focuses attention on her, making her a more memorable opponent. In the center of the ground floor, put some sort of big bruiser (a summoned monster works great). Ideally, choose one that can make multiple attacks each turn, and give him long tentacles or a lasso or some other ‘get over here’ power so the party can’t bypass him. Fighting him will keep a couple PCs occupied. Put some skirmisher-type enemies spread out around the hayloft. They can fire down on the party from above. And, when the PCs get smart and climb the ladders into the hayloft, these skirmishers can serve as speed bumps between the PCs and the wizard.
What sorts of spells should the wizard have?
- First, a couple of buffs she’s cast on herself before combat began – especially spells that will protect her from the PCs’ ranged attacks. This is an ambush, so she has time to prepare.
- Second, something to trap the PCs inside the barn once they enter. It could be summoning a wall of ice in the doorway once they’re all inside, animating the wood of the barn door so it slams shut and holds itself closed, or whatever’s sufficient to overcome the PCs’ resources.
- A few ranged direct damage spells to put the hurt on the PCs.
- Some sort of forced movement spell to knock PCs out of the hayloft.
- A short-range teleportation spell. She can use this to move to another part of the barn if melée PCs reach her. If the PCs are doing better than she expected, she can also use this spell to flee the barn.
- A fire spell. Once the wizard has fled the barn, the PCs are still trapped inside a flammable structure full of hay. Lighting the barn on fire is a good backup plan for the wizard, especially once the PCs are already hurt and exhausted by the fight.
Here are some other cool things you can do with the terrain.
A lot of barns are full of clutter on the ground floor. Some may impede PC movement. Other clutter may make decent cover against the skirmishers firing on the party from above. See the image below for ideas.
That hay in the hayloft is dangerously flammable, but depending on how it’s stacked, it may make good cover too. Rogues can sneak through it, bypassing the skirmishers.
Consider having a pulley hang from a rail that runs the length of the center of the pitched roof. Acrobatic PCs can use the pulley to swing from one place to another. The below image gives a good sense of such devices.
Finally, though the barn has two ladders to reach the hayloft, PCs should be able to just climb up into it as a move-equivalent action, provided they pass their Athletics checks.