Dream of Piers

Dream of Piers (also known as Nightmare) is a non-combat pet in Diablo III, added in patch 2.4.2. Players can obtain it by participating in Season 7 or 19 and having beaten Chapter 4.

It does not engage monsters, but will pick up any gold it runs over. Visually, it is a recolored version of Unihorn.

Trivia

 * The name and description of this pet are a possible reference to the Night Mare by Piers Anthony.