The LSD Trolls are large, ugly humanoids created from hallucinations of D.L. Diamond's "space dust". They appear in the episodes "Don't Be A Negaton" and "Time-Police Part 2".
In Don't Be A Negaton, they appear from the ground. The troll on the left eats a convict while the other grabs a unicorn and throws it at a rainbow. Luckily, the Galactoids appear at the end and blast an LSD Troll carrying a club.