The ending of the first game; Jim makes it to Princess What's-Her-Name, and she puckers up to grant a Smooch of Victory and the cow you sent flying up at the beginning of the game lands on her, knocking them both into a river/pit of lava. Jim mopes for a moment...then grabs her crown and happily wanders off.
The Special Edition adds an extended animation for Jim, pretty much turning him into the wolf from Red Hot Riding Hood as he howls, does an Eye Pop, and hits his head with a mallet repeatedly.
The ending of the second game; And so, having defeated the nefarious COW, our hero, COW, wins back the heart of the lovely COW. In other words, Jim, the Princess and Psycrow — aka the hero, the love interest and the big bad — all turn out to be cows in disguise.
Anything involving a cow deserves special mention (particularly the second game's ending, as mentioned above).
When you kill a lawyer in What the Heck?, they shout out "I'LL SUE!"
Or anytime Jim goes into Large Ham mode. Which would be about 90% of the time.
"''Eat dirt, everyone in the vicinity!! AHAHAHAHAHHAHAHHAHAH!!"
At the beginning of "Conqueror Worm", Jim and Peter are hanging at the Terlawk Mall with The Mighty Hamstinator. However, Hamsty can't get over his habit of stuffing random things in his cheeks, leading to this line...
Jim: Hamsty! Get that cheese hostess out of your mouth! You don't know where she's been! Ishy! Ishy!
As Jim, Peter and Snot have to retrieve the suit.
Narrator: ...But how can our heroes ever hope to get past the sinister guards? (Jim, Peter and Snot calmly stroll by) Peter: Evenin', guys! Guard 1: Evenin'. (beat) Did a giant worm, a talking dog and a smiling booger just go by? Guard 2: Yep. Guard 1:(picking up the phone) Hello, DNA lab? Whatever you guys are doin' in there, CUT IT OUT!
During the fight:
Jim: I've been thinking about this whole "exact opposite" thing. Since I hate losing, you must love it! So why not give up right now? Evil Jim: Oh, don't be so literal-minded.
"Feel the awesome wrath of your own left fist!"
Following this, Jim draws his blaster, only for Evil Jim to effortlessly swat it out of his hand. Cue Jim's meek "Aww, man".
The Enchanted Snail Petting Zoo.
Jim: I think they like you, Peter. Peter: THEY'RE DEVOURING MY FLESH!! Jim: [laughing] Well, that just proves it.
Jim's fruitless attempts to eat a nut log, including boiling it in hot water, running it over with a motorcycle, shooting it repeatedly with his gun, and eventually using it to shatter an unbreakable crystal scepter.
Peter: I don't think that's meant to be eaten, Jim. I think that's meant to anchor ships during storms.
At the beginning of the Christmas Episode, Jim gives Queen Slug-For-A-Butt a present.
Queen: For me? You shouldn't have. (She opens the box which blows up) You gave me that LAST YEAR!
In the beginning, Princess questions who Santa Claus is and what gives him the right to judge who had been naughty or nice. At the climax we get this.
Santa: In my wilder years I was know by another name. (voice suddenly echoes) WODEN! NORSE GOD OF JUDGEMENT! MAY THE NAUGHTY TREMBLE! He proceeds to lay a massive beatdown on Queen Slug-for-a-butt Jim: Yes Virginia, there is a Santa Claus. And he. Kicks. Butt!
At the start of a Running Gag, Jim and Peter are at the International House of Haggis:
Peter:(eating) Hey, this haggis stuff is great! How come no one ever comes here?
Jim:(deadpan) Because haggis is made from the heart, lungs and liver of a sheep, boiled in its own stomach.
Jim's description of Queen Slug-For-A-Butt in "The Wizard Of Ooze" makes fun of the fact she's a slug which is not a insect, but she rules a planet of insects, calling her a "Entomological Thingamabob".
After replacing Jim's suit with a weak replica.
Jim: Leaping out of the way...isn't as easy as it used to be.
Professor Monkey-For-A-Head: That's because you now have only the strength of an ordinary person!
(Jim tackles him)
Professor Monkey-For-A-Head:(wincing from offscreen) Correction...an ordinary...really big person...
Earlier, The Professor explains why he can't make a second suit:
Professor: Monkey-For-A-Head: Well, I could, but the suit's power comes from the Battery of the Gods, and I only had one. I tried to get another, and the gods turned me into a breadmaker.
Psy-Crow: Pfft! You're not a breadmaker!
Professor Monkey-For-A-Head: Oh yeah? Check it out! (strains, a bell goes off and he pulls a loaf of bread from his coat) Actually, it's kinda handy. If I twist the monkey's tail, I can make pumpernickel.
(Cut to a shot of Psy-Crow's REALLY weirded out face)
The Planet of Easily Frightened People.
Ahhhh, a bug! Ahhhh, air!
Ahhhh, something green! Ahhhh, something not green!
Behold!, perhaps the most random thing to ever be shown on this show!... and considering this show that's saying something.
Narrator: Ugh... anyone mind if I skip the transition speech??
Narrator: Of course, the most horrific thing about being the narrator is the degrading hula girl outfit they make me wear.
Narrator: All right, Mart- Marty, listen, you have to get me off this show NOW!
Earthworm Jim: You've gotta help us! Narrator: Not in the mood...
"Bring Me the Head of Earthworm Jim": "Something smells like prehistoric cheese... OH MY SOD! It's ME!"
In "The Anti-Fish," Professor Monkey-For-A-Head attempts to tell a a version of "Little Red Riding Hood" where Jim is the wolf and he's the huntsman who comes in to save the day. Even with the Professor telling the story, Jim still ends up defeating him.
Cut to #4 doing first a one-man marching band routine, and then blowing up a bundle of dynamite jammed in the Anti-Fish's mouth, all whilst Bob continues screaming "Wake up!" at the top of his lungs. After the detonation fails, leaving Bob clinging to #4's tail..
Bob the Killer Goldfish: Hmm. What we need is a noise so horrible it could the dead! #4! Fetch... the bagpipes!