Darwin: Dude, you're gonna make me late!
Gumball: I know...
Gumball: I know...
Gumball becomes jealous of Darwin's talent for playing the slide whistle during Elmore Junior High's band audition, and is accused of sabotaging him before the big game.
Tropes:
- Always Wanted to Say That: Principal Brown cuts Gumball from the parade and says "You won't be raining on our parade.", then admits he had been waiting weeks to say that.
- Artistic License – Music: Darwin easily playing Claire De Lune on a swanee whistle is obviously unrealistic.
- Bait-and-Switch Comment: As Gumball is kicked out of the marching band, Darwin tells him to wait. Gumball seems consoled, but Darwin was just insisting that he hand over his triangle.
- Bittersweet Ending: Darwin botches his performance and likely ruins his reputation as a slide whistle player. Gumball and Leslie, on the other hand, find his downfall absolutely cathartic.
- Black Comedy: The shots from Leslie's flute sound like sniper fire and one of the targets it hits is a slice of Cartoon Cheese who gasps, "There's an extra hole in my chest!" and passes out.
- Blunt "Yes": When Gumball and Darwin are on a bench, Gumball hugs Darwin, then latches his feet to the bench when the bell for rehearsal rings.Darwin: Is this how it's gonna be?
Gumball: Yeah. - Bowdlerise: The Cartoon Network Asia version shortens the part where Gumball steals Archie the Duck's costume while Archie is on the toilet. The Cartoon Network Asia version cuts after Gumball takes the top half of his costume.
- Brain Bleach: After imagining what Professor Small looks naked, Darwin plucks out his own eyeballs, which then grow back. Leslie is horrified vicariously during the same scene (since he was the one who suggested it) and then Prof. Small bends down in front of him too, giving him a direct image to go with Darwin's.Darwin: Nope, I can still see it.
- Cassandra Truth: When Gumball tries to explain that he isn't the one who put gum in Darwin's flute, no one believes him. Not even Darwin.
- Continuity Nod: Gumball's instrument in the band is a triangle, the same instrument he failed to play in a flashback of his week in "The Fridge".
- Crushing Handshake: As Gumball congratulates Darwin for getting a solo, Darwin feels he's being insincere because he's "kind of breaking my hand right now".
- Cue Card Pause:Darwin: You've been jealous from the start, you tried to stop me getting to rehearsal and when you didn't succeed you sabotaged my swanee whistle.
Gumball: Dude, I would never do that... To you. - Dartboard of Hate: Gumball thinks he sees Darwin in a dark room and tries to apologize, but then he discovers that it's really a cardboard cutout full of dart holes. This is what convinces Gumball that someone is trying to sabotage Darwin.
- Department of Redundancy Department: The guy who normally wears the Elmore mascot costume, Archie the Duck, looks basically identical without the costume.
- Disproportionate Retribution: Brown threatens to expel Gumball if he sees him.
- Double-Meaning Title: “The Triangle” either refers to the titular instrument that Gumball plays or the triangle between Gumball, Darwin, and Leslie.
- Epic Fail: Colin and Felix are so terrible at playing their instruments that blowing into them somehow made the tops of their shells pop open.
- Faceless Masses: The audience during the band performance look like indistinct colored blobs because they actually are: the vast majority of the onlookers look like Billy (i.e. basically a paint blob shaped like an egg) recolored and sometimes with a body shaped like a pentagon or square.
- Family-Friendly Firearms: Leslie tries to attack Darwin with a dart blowgun disguised as a flute. For some reason, it sounds like a rifle.
- Fingertip Drug Analysis: Principal Brown wipes his finger across the gum covering Darwin's sabotaged whistle then sticks it in his mouth.Principal Brown: I have no idea why I just did that. It was pretty obvious it was gum.
- Frame-Up: Gumball has been framed for attempted to sabotage Darwin.
- Freeze-Frame Bonus:
- When Darwin asks to audition for a solo, Leslie looks just as mad as Banana Joe.
- After Sussie's tears flood the gym, Teri looks down worriedly, probably because she isn't waterproof.
- Leslie is the one who handed Darwin his whistle before it was discovered it was sabotaged. If you look closely, you can see him sticking the gum in it and smiling deviously as the bubble of gum inflates.
- Green-Eyed Monster: Someone is trying to sabotage Darwin's solo out of jealously; the question is who.
- Hope Spot: After Principal Brown kicks Gumball out of the band and he leaves the gym, Darwin calls, "Gumball, wait!"... and then snatches the triangle back, since it's school property.
- Hypocritical Heartwarming: Sabotage Darwin's instrument? Gumball would never do that... To Darwin.
- Immediate Self-Contradiction: Gumball is content with mediocrity since it avoids failure but becomes highly envious of Darwin when he gains praise.
- I Know Karate: Gumball thinks he can stop Leslie by force after pinning him down and is quickly disproven.Gumball: Dude, you're a flower boy who plays flute in a school band. You don't want this to get violent.
Leslie: You are talking to someone who has danced since the day he was born!
(Leslie gets up and delivers multiple slaps and kicks to Gumball's face while dancing)
Gumball: What I meant was... violence is never the answer. - Ignored Aesop: Gumball and Leslie agree to be happy for Darwin, but they both celebrate when Darwin is too nervous and botches the solo. Though, considering Darwin's behavior towards Gumball throughout the episode, it's kinda hard to blame either of them.
- Imagine the Audience Naked: Leslie gives Darwin this advice to help with his stage fright. Then Professor Small drops his lunch in front of them and bends over to pick it up while talking about playing the bongos. This leaves Leslie and Darwin with horrified looks on their faces.
- Insane Troll Logic: Principal Brown deduces with no other evidence that Gumball sabotaged Darwin's whistle because it was filled with gum and his name is Gumball.
- Instrument of Murder: Leslie tries to sabotage Darwin's slide whistle solo by using a dart blowgun disguised as a flute.
- Jerkass Ball:
- Darwin spends the whole episode berating Gumball and refusing to believe he's innocent of trying to sabotage him. He does pay for it, though.
- Principal Brown also grasps this, assuming Gumball to have sabotaged Darwin's whistle because it was filled with gum and his name is Gumball. He refuses to believe Gumball when he tries to plead innocence and kicks him out of the parade despite the very flimsy at best evidence. Later, he even threatens to expel Gumball if he sees him at the parade.
- Laser-Guided Karma: Darwin’s refusal to believe Gumball was innocent leads to Darwin botching the solo and being booed.
- Left the Background Music On: The episode begins on Coach as sounds happen in time with her movement. She seems to notice this, and the sounds turn out to be the school band in the room behind her.
- Literal-Minded: Gumball says to Darwin with an angry face that on the inside, he's pleased, so Darwin opens up Gumball and we get a flaming supernatural being appearing from the inside of Gumball.I HOPE YOU CRASH AND BURN, DARWIN WATTERSON!!!
- The Man in the Mirror Talks Back: Darwin imagines Gumball in his locker mirror talking to him. Subverted in that Gumball really is in the locker room, being reflected in the mirror.
- Meaningful Echo: Gumball echoes Darwin's words when telling Leslie not to get upset when someone else does better than you.Darwin: This isn't about me being good at something, it's about you refusing to make an effort to better yourself. And you know the definition of that kind of person?
Gumball: A loser?
Darwin: No! Wait, yeah, a loser.
Gumball: Dude, you're supposed to be happy for your friend's success. This isn't about Darwin been good at something, it's about you refusing to make the effort to better yourself. You know what the definition of that kind of person is?
Leslie: You.
Gumball: Exactly.
Leslie: (shivers) I wouldn't want that to happen! - Nerf Arm: Close examination shows the darts from Leslie's blowgun actually have suction-cup tips. Functionally they're not even like pointed darts, they're more like bullets.
- Ocular Gushers: Sussie cries so much after Darwin's solo she floods the gym. Principal Brown warns her to stop before they have to call the Coast Guard.
- Offscreen Teleportation: During Leslie's flute solo he suddenly disappears and then pops out of Sussie's mouth.
- Red Herring: Banana Joe is set up to be the one who is trying to sabotage Darwin's solo, looking angry as he stands behind him with his cymbals raised. Turns out he just looks angry because he's concentrating on playing at the right time, and the real saboteur is Leslie.
- Tall Poppy Syndrome: Gumball resents Darwin succeeding because he figured they could always be losers together.
- Training Montage: Sussie suggests the band improve through a training montage. Principal Brown says they don't even have time for one, so instead he tears the pages off a calendar to simulate one. Somehow, it works, and the band manage to considerably improve in the course of twenty seconds.
- Traitor Shot: Parodied when Gumball tries to figure out who is trying to sabotage Darwin and the camera keeps cutting to close-ups of Banana Joe. He doesn't take the hint even after several zooms, the last of which breaks the camera lens and bowls him over.
- Triangles Are the Worst Instrument: Gumball's frustration at being assigned Triangle kicks off the plot when he feels upstaged because of it.
- Trivial Title: The triangle is Gumball's instrument, but has very little to do with the plot because he refuses to play it and gets kicked out of band halfway through. However, "the triangle" could also refer to how Gumball and Leslie have both targeted, or are accused thereof, Darwin for sabotage.
