This stealth game will definitely test your reactions

In the most desolate, cursed desert you are crawling in the dark, craving for blood...Some believe you arrived from space, others think you are a demon from hell. They call you "El Chupacabra" and fear the biped shadow who attacks by night, sucking the blood out of goats using its sharp teeth. Everybody wants to catch you dead or alive. And you're out of luck unless you master the arts of hiding in the shadows.