I'm not finding anything in the rules about leveling for creatures. I see experience points which would suggest leveling, but was wondering how critter interactions work. I'd assume similar to NPC squading, but yea. So mainly asking: do critters level, do their skills build, etc.
Creatures can gain experience by patrolling and attacking enemies. When they acquire enough experience to increase in level they gain 10% more health and no skill points. At level 10 this means they will have double the hit points of a level 1 creature.