The Chupacabra (literally translating to goat-sucker from Spanish) is supposedly a reptilian-like creature with a leathery gray skin, with sharp spines or quills running down the creature's back. It is said to be approximately 3 or 4 feet in height and is also said to have a stance similar to that of a kangaroo.
Rockstar's rendition of the cryptid resembles a mixture between a hyena and a boar and displays great agility. Other than that, it stays true to the original reports, bearing a greenish-gray skin, red eyes and the creautre has long black spines running down its' back.
The creature can be located around Diez Coronas and Perdido in the Undead Nightmare DLC right after completing level 4 of the Undead Hunter challenges. Upon locating it, the player can kill the creature to obtain its' heart, teeth, claws and its' eye. Killing the creature counts for 4% in the game stats and killing it, along with breaking the four horses of Apocalpyse is a requirement to unlock the Unicorn.