i'll post a video clip once i'm finished editing it, but i noticed around Fall three or so that my game started to slow down and lag a lot. i also saw a nearby hill with three graveyards on top of it, each with two or three winters worth of skeleton goblins roaming around. by winter / spring, the game crashed and was unplayable. i'm not positive, but i think it might be because the game was trying to support too many undead? might be a good idea to have them either stop spawning if there are too many in a small area, or de-spawn if a new winter comes with no interaction from the goblins.
edit: short video clip of all the skeleton goblins at one of at least three graveyards in a small area