I had an idea for a witch doctor spell while I was falling asleep last night.
The spell would animate all of the corpses in an area bringing them back to life. The zombies would all immediately group together in a bunch and would stay stationary in that area. The zombies would start ripping pieces off of each other and hucking them at the surrounding monsters. Zombie arms and legs flying about bonking monsters on the head.... The more corpses that you manage to catch the longer it lasts and the harder it hits. Can you imagine a zombie pulling the head off of another zombie and throwing it...lol
Mechanical The spell would function in a similar sort of way and serve the same purpose as the Diablo 2 Hydra spell.
It probably has to much of a horror vibe to it, but I thought I would throw it out there anyway.