The End of the Universe-ity (S06E10)

Dark Laser returns with a new plan after his previous attempts to eliminate Timmy fail. He decides to take a different approach: if he can't defeat Timmy, he'll try to recruit him instead. He extends an offer for Timmy to attend "Dark-Mouth University," hoping to turn him into his evil apprentice. Timmy declines, but his parents, thrilled at the prospect of free college, enthusiastically accept the offer on his behalf. Given a sinister suit imbued with dark powers, Timmy is told that if he tries it on and decides against it, Dark Laser will leave Earth in peace. Timmy reluctantly agrees, but soon finds himself under the suit's malevolent influence.