The name I gave to this encounter during development was “Zombie Triathalon.” I wanted to see if I could achieve the same “difficulty curve” of an encounter a couple levels above the party by simply using more monsters, rather than high-level ones. I don’t remember the numbers (if you still have your notes, Jared, feel free to post them in the comments section) but there were a lot of enemies in this encounter.

There are two main “waves” of enemies, with a third “half” wave, intended to give the party a jump when they think the battle’s almost over. As they progress through the school, they come to a T-Intersection, where they’re given the chance to spot a weakness in the ceiling before it collapses (they’re knocked down by the concussive force of the collapse, but if enough of them made the check, no one takes damage).

Before the dust can clear, they’re beset on three sides by waves of zombies, including several “brutes” that make enough slashing attacks to make a Cuisinart blush, zombie minions to fill the ranks, and a couple of my favorite: the spore-throwers, which spawn new plague spores that they hurl into the midst of the battle. Whenever one of the zombies drops, they spawn a new plague spore minion (spawners drop two on death) which means the battlefield quickly becomes littered with enemies and stays that way.

Once the worst is over, the party is allowed to proceed, but they quickly find themselves boxed in at a stairwell. They have to weather another, smaller wave while trying to dig themselves out, and on the other side of the debris, two more spawn-throwers wait for them (which dig through on their own if the party doesn’t tend to the collapse themselves). Yay, claustrophobia!