A researcher has come across a frog with an ultra-flexible neck, poisonous skin, and a spiky skull — all of which work together to facilitate a headbutt of death. Or, at the very least, a headbutt that results in hours of what is described as intense pain. The venomous frog was happened upon by researcher Carlos Jared, who didn’t at first realize the frog was dangerous to hold. According to Jared, he picked up one of the frogs and it began struggling and headbutting his hand. He described the sensation as at first being like rough sandpaper, and later on being intensely painful.