A Stage 1 Pokemon Card of type Grass with the title Koga's Muk and 80 HP of rarity Rare evolved from Koga's Grimer from the set Gym Challenge.  It has the attack Sludge Whirlpool with the cost Grass, Grass, Colorless, the energy cost 3 and the damage of 40. It has the ability Energy Drain with the description: If an opponent's attack does damage to Koga's Muk (even if Koga's Muk is Knocked Out), flip a coin. If heads and if it has any, choose 1 Energy card attached to the attacking Pokemon and discard it. This power can't be used if Koga's Muk is already Asleep, Confused, or Paralyzed when your opponent attacks. It has weakness against Psychic 2. 
Koga's Muk