Aquaticism - S7-E14
Continuity mistake: Near the end, when Roger is talking to Judy, he has a tie on. But in side shots of him, he has no tie on.
The Microwave/The Meddler - S1-E17
Continuity mistake: In "The Meddler", Nicole is feeding Gumball food with a spoon and drops it on the table. The camera cuts to Darwin and then back, but the spoon is now gone.
Continuity mistake: When Chris is trying to activate Hummingbird Power, his skin is suddenly lighter than in the previous shot.
Continuity mistake: Chris has a blue dye pack explode on him, covering the front of his clown costume and face. But then shortly after, the dye is gone from his face and clothes.
Continuity mistake: This is supposed to be the Rangers' first mission and we see Jayden use the Fire-Smasher mode of his spin sword. Jayden didn't learn how to use that feature until the third episode of the series, which takes place after this mission.