"I have big plans today. I'm going to chew grass and wait for my nephalem to get back."
- A Unihorn(src)
Unihorn is a non-combat pet in Diablo III, added in patch 2.4.1. It drops from Menagerist Treasure Goblins.
An innocent young girl named Claire discovered this creature. Reasoning that it has a horn and seems to love the unsullied, she decided it must be a unihorn. It's like a horse, but pointy.
Development
Originally, there were two variations of this pet (white-blue and fiery-black), but only one made it into patch 2.4.1. The black version later became the Dream of Piers.