Project Zulu is a minecraft mod that attempts to add flavor to minecraft by adding unique mobs, blocks, and structures to each Minecraft Biome.
Chief among its design principles is configurable content. The mod is broken into 5 modules; CORE, Blocks, Mobs, World, and Dungeon: core is the only requirement for any of the other modules. A 'complete' package containing all modules is also available.
Disregarding the modules, Essentially all aspects of the mod can be disabled and adjusted from the configuration files such Blocks and items being disabled by setting their ID to 0.Mobs can be disabled, or even have the individual spawn settings tweaked.