Amazing turn-based strategy game with a few undead (and sadly less races than the previous AoW SM). However, there's a Necromancer expansion coming up!

It's like that Snake game we used to play on our Nokia phone, but with a conga line made of heroes. Many heroes to unlock, including a Skeleton Warrior.

Pretty much a 2D version of Nethack. Includes a floating skull that gives you tips on how to play, and skeleton enemies too! Demo available.

Gameplay formula of Binding of Isaac translated in FPS form. The graphics and music might not appeal to everyone, but at least it has skeleton enemies.

More than just a 2D platformer with roguelike elements, the combat is as complex as a fighting game's. You can also play as skeletons (and cows)!

A sandbox game where you can do almost anything, thanks to the resources its users pump out. Visit its Steam Workshop, search for BONES, get new pants.

Sadly, this team and class based FPS only has one halloween map with skeletons, called plr_hightower_event. On the plus side, they are green and spooky.