Primitive mobs mod (1.12.2, 1.10.2) adds new mobs to Minecraft. There are tons of slimes you can tame, and they drop tons of unique items. There are many new villages that roam the globe. You can also find chests and attacking tools. Special camouflage armor can be made into any color. You will find new pets and mobs that are chaotic with special attacks. There will be many other strange mobs. You will find fake lily pads and charging blazes as you explore your world. There are even books that can attack you.
This mod adds a variety clever mobs to the game, whether they are completely original, inspired from other franchises, or brought back from old mods.