From publisher blurb:
Old School & Cool Volume 4 brings your game beyond the final frontier—death. Instead of retiring PCs who have been slain or turned by a nasty undead, you can now play your character as they confront their dark nature. Characters can progress along an undead class tree, gaining dark powers as they steadily lose their humanity. Choose from skeletons, zombies, skeletons, or mummies and arm them with powers curated from myth and fantasy.
But there's more. Bring the undead to life with macabre new spells and sinister magic items intended specifically for undead creatures, or flesh out your mundane skeletons and zombies with exciting new tables. There's a complete necropolis—a terrifying city of the dead—replete with maps, keyed locations, undead NPCs, adventure hooks, and more that you can drop right into your campaign!
Finally there's a one-shot adventure The Netherworld, where you play villagers who must enter the lands of the dead in search of lost friends and loved ones.
It's spooky.
It's eerie.
It will terrify you to your core.
It's Old School and Cool, volume 4.