The one horn rat is a creature that created by maxis, present in the final game. You can find it only in the creature stage.
One horn rats are big rat-from creatures, that have 2 legs, 2 eyes, a mouth and one horn on their head. they have pink color.
One horn rats are herbivore and natural creatures. They don't have good attack, but they do have nice sing and dance abilities for the first creature stage packs.