Roguelike Dungeons Mod for Minecraft 1.9/1.8.9 is inspired by super-hostile maps and roguelike dungeon crawlers. It adds insanity of destructible/buildable terrain to the game. Fundamentally the gameplay is vanilla, with the changes mainly being to the world generator.
Download link: Roguelike Dungeons Mod for Minecraft 1.9/1.8.9