The Goat is one of Sam's animals, he appeared in Green Eggs and Ham. He is seen with a few dogs chasing a fox. In the Netflix series, he is a bounty hunter sent by Snerz to speed the Chickeraffe's arrival to him.
In the original book and the 1973 TV special, the Goat was just a normal animal that was harmless. Whilst in the Netflix adaptation, Goat is more of an antagonist. Which would make him the first Dr. Seuss character to be adapted into a villain.