Gravestone mod adds a gravestone to the game, which “spawns” at player/villager/dog/cat death. Also this mod generate cemeteries in some villages, and a “Wither’s catacombs”. This is a new huge structure, like stronghold, where you can find a lot of loot, dangerous adventures and a “Wither Boss” at the end.
Download link: Gravestone Mod 1.8.9/1.7.10