Water Eggman (ウォーターエッグマン U~ōtāegguman?) is the second boss of Sonic the Hedgehog 2, which the player fights at the end of Chemical Plant Zone Act 2. To defeat Water Eggman, the player has to hit the Egg Mobile eight times. Water Eggman is mostly an Egg Mobile with a tube-like crane that releases Mega Mack. It is mostly grey, and has black and yellow stripes. It is piloted by Dr. Robotnik, who will try to drop the Mega Mack on Sonic's head after filling up the entire tank.