Episode 66 has this moment. After he fails at grabbing the last Green Star, he ends up seemingly falling to his death, only to grab the previous Green Star on the way down. The last 2 minutes of his commentary set it in stone.
Great Mighty Poo: How about some scat, you little twat? NCS:What!? Oh nonononono, don't do it now! I already got enough shit being thrown at me— waitwaitwait, B Pad! *activates* *Conker pulls out a giant roll of toilet paper* NCS:WHAT!?GET SOME MORE TOILET PAPER! AAAAAHAHAHAHA! GET SOME MORE TOILET PAPER! YES! NO WAY! I actually get to use toilet paper!
To the end:
NCS: WHAT WHAT, WE'RE NOT DONE YET!? OH JEEZ LOUISE, MAN! WHAT THE HELL!? ...wait a minute, though! Was that— was that what I think it was? Do I actually get to flush him down? After all that, I get to flush it? Ohh, wouldn't that be amazing, please tell me they did that! Y'know,IN THE BATHROOM! They had to have done that! There is no way they wouldn't make that the way that you finally finish him off! It has to be! ... *Conker pulls the flusher* Great Mighty Poo: Ah, you cursed squirrel! *flushing sound* NCS:YES!GET SOME MORE TOILET PAPER! *spends the entire last minute of the video uncontrollably laughing his ass off*
The fact that he has an In The Bathroommeter in the Conker LP. Occasionally, fans will leave comments saying "Ding!" (the meter noise) or just mention the meter whenever he says "In the bathroom!" in other LPs.
Anytime he pulls off the infamous Green Rupee Scream.
In his Plants VS Zombies LP, he said how every composer's dream is to put lyrics about taking a crap to beautiful music. He then sung a song about sitting on the can to Beethoven's Fifth. And it is awesome.
In Skyward Sword 6, he doesn't know what kind of voice to give the mysterious person in the temple, so he just gives them all of them at once.
While looking around for the Kikwis in Skyward Sword, NCS is completely oblivious to the crow flying around Link... Then he realises it's actually taken a crap on Link's head.
Most of his LMAOnote Let's Mess Around On Mario Party 2 videos are hilarious— particularly the second board, where he semi-consistently refers to the NPC Mario and DK as ProtonJon and Chuggaaconroy. A lot of what happens there doubles as Hilarious in Hindsight for The Runaway Guys' play through of MP2.
NCS dissolves into making Call Backs or shouting Catch Phrases on behalf of his missing companions. Highlights are:
" And I'm in last place. Feels like home. Just kidding..."
"Have a bomb, Chugga! Look at Proton and Chugga passing it back and forth! This really is Proton and Chugga..."
His commentary while on a team with NPC DK/Prugga, and beating the others
NCS: SUCK IT TREBECK!
" Chugga's got a mushroom. No further comment there."
"Hey Chugga, don't eat the mu—" [dissolves into laughter]
Him taking over for Jon when NPC Mario/Choton gets screwed over.
During the first episode of NCS's LP of New Super Mario Bros. Wii, he and a guest-star spend several minutes looking for a secret pipe to a hidden bonus area. Cue NCS just casually standing on the pipe they were looking for without realizing it.
Mario holding onto a Bob-omb promting this response-
Chibi: (While Mario holds said Bob-omb) No, we can't keep it!
Them trying and failing several times to defeat some Ice Bros in a bonus mini-game.
In one episode of the Skyward Sword LPnote "You Ain't Nothin' but a Fetch Quest" NCS sings the Ballad of the Goddess's lyrics... and belatedly realizes that he wasn't singing them to the tune of the Ballad of the Goddess, but to the Great Mighty Poo's song. When the second verse comes up, he goes ahead and sings that the same way.
Upon encountering a glitch in Donkey Kong Country 3 wherein Dixie Kong flies to the top of the screen after he falls into a pit and dies.
In episode 2, after getting the Running Shoes, he finds it so mind-boggling that the shoes would come with instructions that he proceeds to laugh uncontrollably for about 30 seconds.
Mother: NCS, those shoes came with instructions.
NCS (laughs his head off): Do you really need instructions for shoes?
NCS talks about Game of Thrones and mixes up the name Westeros with "Westboro".
Any time NCS decides to read out the in-game dialogue but replace it with something he thinks is better, such as:
NPC: I am Mr. Stone, President of the Devon Corporation.
NCS: "I am Obama, President of the United States of America".
Tim seeing the Pokémon Nuzleaf for the first time:
NCS: "I am the almighty tiki god! I wear a bra on my legs!"
His reaction to seeing Kirlia's back sprite.
In episode 30, when confronting Norman (the player character's in-game father) NCS comments "I may not be able to beat my dad at Dr. Mario, but I'm sure going to beat him at Pokémon!" He then adds that his Real Life father is a master at Dr. Mario and can get up to level 50.
Tim's post-edit pop-up messages in episode 43 where he constantly corrects incorrect statements he makes in the video.
In Episode 51, the best use of the Green Rupee Scream - after trying to catch Regice, it runs out of PP and kills itself from struggle recoil. His reaction is priceless.
He finally manages to catch Regice (or as he calls it, "Regis Philbin" when he plans to use 30 Ultra Balls in order to max out the effectiveness of a Timer Ball. He does so, only for the Timer Ball to fail. And then, as he despairs, the next Ultra Ball he throws randomly catches it.
His... enthusiasm when getting the Chili Bean in Plants vs Zombies 2. For the record, the chili bean makes your enemies fart. Which kills them.