Gimpy setting up his room so that he never has to leave. Ever.
The Risk episode, on so many occasions:
The guys are in a Risk game, and Rocko has been defeated, whilst Cal is so completely inept that he a) doesn't realise that Nitz and Gimpy have called a truce against him (keep in mind, when the truce was made, they openly discussed the terms in front of him, and pose for a photo op with the signed documentation) and b) he's tangled up in a sleeping bag. Meanwhile, Nitz realises the only move he can make is to attack Gimpy, so he does. Gimpy sees this as the ultimate act of betrayal, and retaliates with a kamikaze attack. Nitz then points out how stupid this move was, as Cal's forces now outnumber their forces so greatly, they have to surrender.
The mere fact that the reason Nitz doesn't want to play Risk specifically is that Gimpy always gets beaten to the point that he starts screaming "KAMIKAZE!" and launching suicide attacks on everyone, which always results in Nitz winning.
Gimpy calling on Mump to serve as his technical advisor over radio and watching over surveillance camera.
And finally, the revelation that the festival at State U has disintegrated into a flaming warzone, all because Nitz was playing Risk, instead of being at the festival to stop one very minute thing from happening.
Gimpy sends Mump in his place for Christmas so he doesn't have to leave his room.
"I'm out of the will, but it's worth it."
From the first episode, when Rocko hallucinates Mump as the Great Gazoo:
Rocko: Oh Great Gazoo, what should I do?
Gazoo: Continue making a jolly old ass of yourself.
"Good evening ladies, you want some sex in exchange for... sex?"
The title of Rocko's self-made book: "Things Cal Does That Make Me Want To Kill Him Dead Dead Dead Dead DEAD!"
The gang attempting to find free sources of entertainment while their source of income has dried up, which ranges from sneaking into a Jewish sabbat dinner, to attending a crappy christian rock concert.
The clique completely falling apart while Nitz is in self imposed exile in his room as Room Guy. Without Nitz to guide them, Rocko has used negative conditioning to turn Cal into a carbon copy of himself and then descended into madness because Cal not being annoying anymore meant he didnt hate him, which went completely against his world view, Cal has turned feral and decided to live among the squirrels because his new Rocko/Cal persona means women are no longer interested in him, and Gimpy has become obsessed with obtaining Nitz's fame as Room Guy for himself.
Nitz attempting to create a defining identity for himself to make himself noteable to the other students, which consists mostly of grafting the identities of everyone else into a single personality.
Also from Identity Crisis, we have Gimpy's increasingly desperate attempts at luring Nitz out of his room, including sending out his sidekick, the portly Mump dressed up as Nitz crush Kimmy.
Mump: "Oh Nitz, its me, Kimmy Burgen, your one true love! Please come out of your room and make sweet love to me!"
Nitz: "No, Mump!"
From the last episode, Screw Week, we have the incredibly crappy student housing the group comes across while looking for options of where to live next semester, such as a cardboard box without water, electricity or air which cost 3000$ a month, and a dillapidated town house with most of its ceiling missing, and a broken toilet.
This gem from Cal about being a mascot.
This costume gives me great power. Power to install school spirit and make people cheer. But with great power comes great responsiblity. I'd be letting the school spirit down if I didn't show, and the school spirit is a ghost who will kill me if I fail. Ghost's are scary guy.