LotsOMobs
LotsOMobs is a modification for Minecraft. The mod adds a ton of new mobs, items, dimensions, biomes and blocks. You can find everything from tiny little ants and cockroaches to huge T-rexes and other dinosaurs. The most mobs can be found in the overworld, but there are also ancient mobs, like dinosaurs, sabertooth tigers and mammoths. These can be found in the Dino and Ice dimensions.
LotsOMobs is written by TheLarsinator. You can download LotsOMobs on www.LarsMods.com