Spike the Bully Snail made an appearance in the episode "Gary in Love." He works for Mary's Ex-boyfriend who's name was Boss. When Gary saw Mable Monica and her pet snail Mary on the boatmobile and decided to slither after it on the street, Spike the Bully Snail grabbed him by the tail. Gary was surrounded by Spike the Bully Snail and Dan the Orange Snail. His spikes get stuck in the fence when he tries to get out through a gate hole.
(Struggles to get through the gate hole but the spikes on top of his shell is getting in the way) "Hey, how come we never go to the front, guys?"