Although the Grass Snake rarely bites, it can put on a seemingly aggressive defence if cornered, inflating the body, hissing loudly and striking with the mouth closed. On occasion an individual will adopt a completely different form of defence by feigning death. This very convincing display involves the snake writhing onto its back, the body becoming flaccid and the mouth open with the tongue hanging out. If further provoked or caught, they will struggle violently and discharge an evil-smelling fluid from their vent.