Deals Bonus Damage to Poisoned enemies
Muk can deal bonus damage if the opponent is poisoned. Poison can be inflicted with Grimer or Weezing, so if you use Muk, try to organize your team with cards that can poison the enemy for you.
Aim for the Koga and Weezing combo
To poison your opponent, it is also effective to aim for the Koga and Weezing combo. After poisoning your opponent with Weezing's ability, use Koga and send Muk to the battlefield, and you can use Weezing as a shield while attacking your opponent.