Muk

Muk now is a shapeshifter, he can take on his own human form or keep up with his own original form as he likes. He has learned some moves of basic slime abilities serving for his shapeshifting, liquefying and mass-control like “Transform”, “Substitute” and “Acid Armor”. P/s: If in the anime, a rarely Meowth in Team Rocket can talk, then imagine this as well, your Muk learned how to transform the same to Ditto.