Given that Arino's a comedian, things getting funny is only a given.
* In the first attempt at playing the ludicrously hard VideoGame/SuperMarioBrosTheLostLevels, Arino makes it past level 8-2's "Triangle Paratrooper Jump" (Where you need to time a jump on a Paratrooper just right such that you hit a block to open a way to the last part of the level (in the form of a vine), needless to say, this took up a fairly large chunk of the challenge) only to miss the last jump, just centimetres away from the end level flag. The pure inhuman scream that Arino emits is hilarious.
** Before starting on Lost Levels, however, he's shown attempting the original game, and failing to do the infinite 1-ups trick. After repeated failures of it, the episode cuts to two-and-a-half hours later where...he's still trying to get infinite 1-ups.
** During the second attempt at The Lost Levels, a young genius gamer named Kazuki Akita, along with his father and younger brother, visit the show to help Arino clear the game.[[note]](Kazuki had also sent the show a videotape showing the [=GameCenter=] CX crew an easier way to clearing the Triangle Paratoopa Jump)[[/note]] The funniest part comes upon reaching World 8-4, when Kazuki asks Arino if he used any warps. When the Kacho admits that he had, the genius gamer immediately hit the reset button, much to Arino's shock.
* In Lemmings, after figuring out that you can't save all of the Lemmings if you use some as blockers, he starts naming the unfortunate lemmings after AD[=s=]. This got silly right about the time he was screaming "TOJIMA!"
** Then, at the end, he started extending the challenge past what was called his "Last Lemmings." The name evolved into stuff like "True Last Lemmings" before finally winning on "Return of Last Lemmings."
* While playing ''Balloon Fight'' as Satoru Iwata watches, the Nintendo president explains to him how things in the game work, such as the fish who is always moving around the screen and so may or may not appear when the player goes too low. He then says he knows those things because ''he'' programed the game.
** Iwata later tries to catch 20 balloons in a row. He does well but fails, and thus Arino is the one doing snarky praises to the game's maker: "Well done, sir! You need luck to stay up. Nice! That was very clever."
* In the ''VideoGame/ParappaTheRapper'' episode, Arino dons some [[https://s3.amazonaws.com/data.tumblr.com/tumblr_melijx2Kjw1qbgeh8o1_1280.png hip hop style clothes]] for the final stage.
* During the ''Dig Dug II'' episode, Arino goes to a toy store in which he plays slot car racing with the staff. Near the end, [[OhCrap his car flips over]] and... ''is pushed to victory by the second car''. The third car then ''also jumps over to push them''.
* In the PunchOut episode, AD Emoto offers to fight Soda Popinski, with Arino serving as his "second". Every time Mac gets knocked down, Arino throws in the towel. Emoyan ultimately loses by TKO, and just to further rub it in, [[EvilLaugh Arino laughs like Popinski.]]
* ''[[VideoGame/GhostsNGoblins Ghouls 'N Ghosts]]'': Arino makes it to the stage 1 boss much sooner than previously (contrast to ''Ghosts 'N Goblins'', where it took him 5 hours to do the same), and cheers that he's about to clear the stage... only to get a glimpse of the huge boss and immediately run away screaming.
* The live ''Takeshi's Challenge'' challenge featured Inoue repeatedly doing an impression of Takeshi himself, much to everyone's chagrin. Then, during the karaoke part, Nakayama tells Inoue and Arino that all they have to do is sing really loudly. You can guess the result.
* During the journey for the northernmost arcade game in Japan, we're told they didn't find any games in one town, so they'll keep moving north. Arino has this silly yet sympathetic look of great despair, which is how anyone would feel when visiting malls and stores in search of arcades and game kiosks, only to find none.
* Arino plays an assorted set of challenges from ''VideoGame/NESRemix'' with three children, showing how exhilarating that kind of multiplayer can be ([[HypocriticalHumor such as when he taunts the kids when they lose]]) while also serving as an effective advertisement for it.
* The Game Center CX in Asia episode features ''VideoGame/SuperMarioKart'' for the challenge. He isn't able to clear the objective of finishing every course, so he plays the usual 5-round match against the staff. The last match is against now-director Inoue, who is on par with his skill (read: low), on [[ThatOneLevel Rainbow Road]]. Even the narrator foreshadows the chaos that predictably ensues.
* On the DVD cut of the ''NinjaGaiden'' episode, as time runs short on the first day of the challenge, Toujima warns Arino that "this is no laughing matter," to remind him of his schedule. Arino answers by making a fart sound, instantly destroying the serious mood Toujima was trying to set.
* The ''Super Mario Land'' challenge. Kibe forgets the script for the episode, and the first part of the episode is a massive running gag about it. Later, Arino decides to call Kibe, who reveals that he completely forgot it because Takahashi was distracted during their meeting. In addition, Kibe spoils the length of the game to Arino, followed by a blunt "Wait. Was I not supposed to say that?" Everyone's reaction is priceless.
* In the ''The Fifty-Three Stations of the Tokaido'', AD Tsuruoka sings lyrics set to the melody of the stage's music. When he gets too a certain line, he starts singing a little too high. Arino stops him and mocks him with the same high pitched line and as a result the staff won't let him live this one down.
* In the ''Super Spy Hunter'' challenge, Arino is struggling near the end of the game, so Takahashi informs him of a code that nets him 20 lives. What he ''doesn't'' tell him is he has to earn them by playing a Pong clone called ''Hyper Tennis''. Beating the computer gives him the 20 lives, failing the minigame ''changes his lives to zero.''
* During the Super Mario Bros 30th Anniversary Special at NicoNico Chokaigi 2015, Arino challenges two Japanese Let's Players to ''VideoGame/SuperMarioMaker'' levels he made himself. When they sit down, Arino questions them as to why they're both wearing masks, since they're not actually sick. He adds an additional bet saying if they lost, he could unmask them. He then decides to join them by putting on a mask as well, only to reveal it's a Comic/CaptainAmerica mask.