The Emperor's New School
Kuzclone
S1 E8:
When Kuzco realizes he's the only person without a best friend he is pretty bummed out. But then he thinks it's his lucky day when he meets an exact replica of himself - whom Yzma brought to life with one of her potions in order to sabotage Kuzco. Unfortunately he's there to destroy Kuzco's life, not be his best friend.