Rocky

"Pet collectors will also be thrilled to befriend a new cosmetic pet&mdash;Rocky is a regular chip off the old block, and he’ll be happy to rumble along and pick up your gold as you adventure through Sanctuary!"

Rocky is a non-combat pet that is available for those who participated in Season 9 and 21, as a reward for beating Chapter 4 of Seasonal Journey.

In-game, he will collect gold for its master. Intentionally or not, this earth elemental creature was included together with Might of the Earth set from Haedric's Gift and the earth-themed Season portrait.