While Ben and Rook are visiting the alien city, Ben is consternated to see Rook apparently mistaking a kid's balloon for an alien and trying to interrogate it. Then, as he turns his back, it turns out the balloon is an alien.
When one of Psyphon's henchmen accidentally brought Ben and Rook to their lair:
Psyphon: You just led Ben right to me. I don't know if I should thank you or eviscerate you.
Henchmen: Ew... thank me?
Psyphon:(shocks him) Thank you.
When Rook takes down an enemy:
"I'm sorry, I haven't got any witty remarks."
When Ben tries to take down Khyber's pet on his own and insisting Rook does not help, he completely fails to do any type of harm. Rook's reactions sell it.
Rook's various clueless remarks throughout "A Jolt From The Past."
Also, Ben commenting that it took Khyber five years to capture him, while it only took Vilgax five minutes.
In "Many Happy Returns", Gwen and Kevin return for an episode. Of course, this means that Kevin's car also returns, bringing back a running gag in the process.
Kevin: (After his car gets destroyed, yet again) Aah! My ride! What is it about this town!?
Later in the same episode, Kevin reveals he used a Tetramand indestructible engine for his car, thus explaining why it has always survived all the wrecking.
And this pearl arrives during the fight between Looma and Ben:
(Gar starts crying)
Looma: Father? Are you hurt?
Gar: No, it's just... this is how your mother and I met...
The episode opening is pretty much 2 solid minutes of hilarity as Ben ends up having to use Rath to save a little girl from a house fire. Highlights include Rath picking a fight with the fire (and clocking himself in the face in the process), the little girl complaining about how Brainstorm is cooler while Rath is saving her, and Rath having to go back inside the burning house to retrieve a doll.
Rath: Lemme tell you somethin' new Omnitrix! Even Rath knows that this is not a job for Rath!!
Another funny part is when Kevin, Gwen, and Rath are getting out of the building. Kevin and Gwen just jump, but Rath has to do a roll... which is just when Ben transforms back. Stuck with the forward momentum already there he ends up sliding on the ground and having to use Kevin to stand up again.
In "Gone Fishin", Rath hates water. How much does he hate it? He undermines his own and Rook's rescue by giving a waterfall a "lemme tell you somethin'" speech.
From "Gone Fishin", Ben and the gang are less than impressed with the robot pirates' plan of bottling ships.
Ben: (unenthusiastic) Your...ship-bottling days are over.
And then after that, when Blukic decides to stop running away from the robomice, Driba says that this happened last time he got spat out by an elephant.
Rook looked FAR too happy at the prospect of continually dunking Ben into the water "for a good cause". He's never smiled wider in the series... so far (Malefactor)
In the same episode, a kid asks Ben to transform into different aliens so he can dunk them. So he quickly goes through guys like Stinkfly and Spidermonkey, but Humongosaur? When he gets dunked, there's no splash since he's taller than the tank.
Kid: I bet you aren't even the real Humongousaur, you're just a guy in a suit!
Humongousaur: Dude, you just saw me transform!
In "Arrested Development", Ben and Rook have been de-aged into kids. Ben looks just like himself back in the original series, but Rook? Let's just say he has a very fluffy tail and leave it at that.
Also, since Ben was de-aged the new Omnitrix isn't calibrated to him. So Ben has to rattle up info about him to make the Omnitrix recognize him. How does he end his spiel?
Ben: "I'm scared of peacocks!"
Ben complaining to Grandpa Max about being a kid, and Grandpa Max trying to console him. Ben reminds him that he's still 16 and wishes to be treated that way.
Grandpa Max: Oh. In that case... Stop whining Ben, act your age.
The alien Radio Drama about Ben, and its rather... unique take on his adventures. Such as his sidekick, Gwevin the space chimp.
At the end of the same episode, Ben was tricked into wearing a dress.
In "Ben Again", younger Ben reacts in his usual disgusted way when he's told that he frequents Mr. Smoothy's in a few years. This is utterly one-upped when he realizes that older Gwen is going out with Kevin 11.
Pretty much anything either Gwen does in the episode. In particular, the way she finds herself falling back into her old ways of dealing with Ben.
Or younger Gwen freaking out about Ben being so nice to her.
Ben: I miss you alot
Gwen: Miss me? (Gasps) Am I dead? I'm dead, aren't I?
" Store 23" gives us Ben 23's terrible names for his aliens.
Original Ben, as Heatblast: I call this guy Heatblast.
When Blucik, Driba and Hokestar get noticed by people in Dimension 23, the police arrives and threatens to shoot if they don't get out of the Mr Smoothie. Hokestar's reaction? Putting the Closed card.
The Ben we all know and love goes to Mr. Smoothy for a snack break? Where does Ben 23 go to? Mr. Gyro.
Dimension 23's Azmuth gets some good snark in. Like his telling Bluckik and Driba that by Earth standards they're brilliant scientists... but complete morons by Galvan standards.
Doubling as a Radar moment, "Our" Ben tells Ben!23 "If you're done stoking your demand..."
The episode "Special Delivery".
Special note goes to the on-screen debut of Toe Pick: His face is so hideous it has Psyphon begging Ben to stop using the alien.
Then there's that whole fiasco with Mr. Bauman's van. Several years ago, Ben ended up chucking it into orbit. In the present Ben accidentally brings it back down. On top of Mr. Bauman's house. After this Ben flees in fear from Mr. Bauman by running to his house... which is right next door to Bauman's house.
The beginning of "Showdown Part 1" features Ben and Rook chasing after Pakmar's truck, thinking it's on fire, only for Pakmar to say it's a barbecue and saying Can't You Read the Sign? (which unfortunately was in alien writing).
The second part of "Showdown" gives many scenes to Kevin and Khyber's pet. A highlight is the scene after they first meet. Metalized Kevin walks toward his destination while dragging the pet behind him, its jaws firmly yet uselessly clamped on his ankle.
Kyber's pet is a female. The fact no one else realized this makes Kevin wonder if they paid any attention in health class.
The explanation of why Rook would prefer the females on his homeworld to Gwen, which ends with Ben and Kevin shoved out of a jet in midair.
On the way down Kevin gets upset that Ben still hasn't figured out how to work the new Omnitrix.
After that, Ben accidentally crushes Malware as Waybig.
Don't forget the scene where Pakmar goes to Grandpa Max to complain about Ben and shows us a Long List of complaints.
"You! Colorful shirt man!"
Almost all of "Tummy Trouble", from Rook shaking off the cat girl's hypnosis at the beginning, to pretty much everything with Upchuck's people. Including a shout out to A New Hope where Ben pretends to be one of the invaders over the intercom. It works.
When it's revealed that "Plan Omega" was to eat the entire planet rather than let the invaders take over. Ben's incredibly baffled reaction sells this particular moment.
Even funnier? He decides to join in, turning into Upchuck and helping.
Vilgax and Ben getting their snark back on during "Vilgax Must Croak".
Ben also get two particularly funny lines:
Ben: Hey, Attea! I have a question! If a guy kisses you, will you turn into a princess?
Ben: Eighteight, uh? Any relationship to Sevenseven or Sixsix? Cause you resemble them... (Eighteight gets suddenly mad) In a good way!
When Ben points out that his getting the Omnitrix started a long tradition of Vilgax getting his butt kicked, all Vilgax has to say is a rather quiet, "No it didn't..."
Isn't anyone else going to mention how, in "While You Were Away", we realize that the reason Revonnahganders don't use contractions is because they view it as something between bad grammar and cursing? This makes rewatching the scene where Rook, Ben, and Young One interact with Rook's brainwashed family twice as funny. Not to mention this little exchange that takes place once Shar and Sheriff Wat-Senn are no longer under mind control.
Young One: Shar! You're back!
Rook Shar: Language!
Young One: Forgive the contraction.
Ben, alias Bullfrag, flirting with Attea.
Gwen figured out that Bullfrag was Ben because only Ben would go around using a name like that.
Rook admires Kevin's fighting skills. Gwen is less than amused.
"Hate to ruin a budding bromance, but we've got stuff to do!"
Argit taking down a Way Bad in a moment of panic. The aftermath leaves him naked and bald.
Bystander:You're a hero!
Argit: Yeah, thanks. Now, can you get your hero some pants?
Milleus ranting at Attea for successfully outgambitting and betraying him right before tearfully saying "they grow up so fast".
Kevin's irritation that everyone except him figured out that Ben was Bullfrag.
"Rules of Engagement" manages to capture the entire Harem Genre in a single episode. Highlights:
Looma is defeated in the end by Julie herself. In a manner that involves Ben getting served.
The story behind why Ben and Julie broke up for real.Ben was playing a video game when he gets a call from Julie. She thought he was saying mean things to her when he was really trash talking the game. Nice prioritizing, Ben.
The main theme of the episode can be summed up with this exchange:
When the Gracklflint EATS Pax's top half, there's a shot of Ben and Rook's reaction. While Rook's eyes are bulging and his jaw is dropped, Ben just has this, "Seriously?" face on.
Dr. Animo taunts Ben, Gwen and Max through a TV screen. Gwen pulls the TV off the wall with mana, and then Ben as Wildmutt threatens to pee on it. Max's response:
"We haven't got time for that, Ben."
Ben's crush on Drew Saturday in "T.G.I.S."
Zak Saturday: Dude! That's my mom!
The first meeting of the Saturdays and Ben.
Ben being ticked that no one told him that the Saturdays were called in.
Ben and Zak's conversation on how it's hard to catch up on their TV shows and save the world and such, with Rook not getting it, and Ben excuses him, saying that Rook had grown up on a farm, a serious farm.
Mr. Bauman saying that some rare alien food item he got didn't grow on trees, only for Rook to say that theydo, and Mr. Bauman saying that that wasn't the point.
When Ben merges with Kevin's car as Upgrade, giving it the ability to fly, Kevin asks why Ben hadn't done that ages ago. Ben replies that Kevin had told him never to touch his car.
When Ben uses the car to form a giant robot equal in size to the combo of Rook's ship and the stolen cars, Rook tells him not to damage the limbs, since the cars they were made of were worth more than planets. Ben asks about the body and Kevin tells him to go to town.
Despite the Fridge Horror, "So Long and Thanks For All The Smoothies" has some genuinely funny moments, such as Argit's complete Freak Out when the Anihilarg is activated.
Argit (while jumping from peoples shoulders): Why are you all standing around? Somebody has to stop this from happening! The- THE UNIVERSE IS WHERE I KEEP ALL MY STUFF! (Grabs Ben's hand and slaps it against the Omnitrix)
The complete Lampshadefest on Albedo using several villain stock phrases, of which Ben gets really annoyed by.
Albedo: There is nothing wrong with the classics.
More importantly, Ben pointing out Albedo got what he wanted and could just leave live his life. Cue Albedo answering this:
Albedo: And what? I am supposed to just forget the imprisonment? The humiliation? And the... (shiver in rage) CHILI FRIES!?
From the same episode there's... just about everything Ben says while transformed into Ditto. It's almost like watching an episode of Animaniacs.
After Albedo is defeated, Rook unintentionally uses a stock phrase, and Ben jumps all over it. Albedo has an opinion on it.
Ben: Eh, you had to be there.
Albedo: I was there. It's still not funny.
From "For A Few Brains More", Khyber being terrified by Pesky Dust. And the discovery of its power: a dream sequence of Khyber as a protagonist in classic Ben 10.