In episode "Bride of Swamp Monster", a broken Cartoon Network sign (with letters missing), can been in Kev's Curio shop while swamp monster is speaking to Kev.
This is a blatant homage to the universal monsters Frankenstein, Creature From the Black Lagoon and DC's Swamp Thing. The episode title bares a striking resemblance to Bride of Frankenstein and the font is familiar with the universal monsters movies. The idea of the Swamp monster kidnapping Muriel to become his bride is a mix of Bride of Frankenstein where Frankenstein wanted a bride and how the Creature wanted a woman as well. Swamp thing is mainly due to resembling the same creature and coming from a swamp. It is possible in some depictions of Swamp Thing he wanted that similar love and affection from a bride as well after being cursed with such a form.