Sun Wukong
First appearance:

Second appearance:

Final appearance:

Macaque
First appearance (before powers were taken) :

Final appearance (after powers were taken) :
(Mini fact: the black scarf around his neck is an old scarf that was given to him by Sun Wukong after he took his power)

Obsidian/Red Son:
(First appearance)

(Second appearance) - (Red Son again)

Monkie Kid:

(The rest of the characters in the show hasn't changed in appearance)