A Venom Counter is a type of counter used exclusively by "Venom" monsters and their support cards. In the anime, a Venom Counter takes the form of poison and transforms into a water snake that attaches itself to a monster and bites it, inflicting poison to the monster it attached itself to. These counters can be removed to inflict effect damage with "Venom Burn" or remain on monsters to reduce their ATK and potentially destroy them, though the latter tactic will only work while "Venom Swamp" is on the field. These uses are accomplished with separate card effects.