Merlin

Stitch the word Buffoon onto all his cloths

Show a frog to Uther and say "look what Merlin did to your son"

Switch his magic book with a book entitled sorcery for dummies

Tell him Arthur is replacing him

Make him wear a dress

Tell him Gwen loves Arthur.

Tell him Murdered is planning to attack you with a pink bunny

Give Morgan a puppy name it Arthur

Tell Him Morgan is a better sorcerer

Bust him next time tries to perform surgery