Bizarro Episode: "Hyralious, Mutant Monster". Ken Jeong in every role, even playing a poorly costumed Kaiju/offensive Asian stereotype. In addition, it is the only episode without conventional opening credits and the aforementioned Kaiju turns out to be a live-action man in a suit.
Fridge Logic: Why didn't Lawrence just find a Frankenhole that transferred him earlier than the night of his cursing? He could've warned Barbara, past-him, or hell, both of them to stay the hell away from the forest that night.
I Am Not Shazam: Gandhi initially doesn't believe Dr. Frankenstein is the doctor because he doesn't have a square head or bolts in his neck like the monster Frankenstein.