Rowan: Init 21, Simon: Init 11, Jakob: Init 11, Aeron: Init 7, Korgan: Init 2
(Turns out, half-damage is rounded down. That will take effect next combat)
Rowans' rapier stabs a rat and bounces off the floor and bisects another rats' neck. 2 damage.
Simon charges fearlessly at the rat swarm, and misses completely. The rats are laughing at you.
Also, check to stay upright. (DC 5 Dex check or fall down, DC 15 to run without falling, DC0 if you just take a five-foot step.)
Jakobs' arrow-swarm attack anihilates the rat swarm! Flamey Doom! (1d6=2)
Aeron exercises common sense and does not shoot a rat corpse...Unless he wants to.
Korgan does not slam the door, as there are no living rats on either side.