YMMV / Super Mario Bros. 3Mix

• Game-Breaker: Have the need to take some extra hits, or otherwise need a skill not provided by small or Super Mario / Luigi / Toad? If you're by a door, entering and exiting it makes power-up blocks respawn. While this isn't terribly devastating, it helps in a pinch.
• Good Bad Bugs: At the end of Isle Delfino, Bowser Jr. will occasionally use his attacks on himself after you land the first hit yourself. The boss itself is rather hard, so it's quite helpful when this happens. Unfortunately, its usefulness is diminished by its unpredictability.
• Hilarious in Hindsight: Toad is Promoted to Playable in this hack. In the Super Mario Bros. 3 mode of Super Mario Maker 2, he and Toadette are playable.
• Nightmare Fuel: The unsettling and generally off nature of the music and secret levels in World 0 can catch first time players off guard, as well as the warp between worlds 2, 4, 6, and 8 to 0, how the happy coin heaven music transitions into a hellish nightmare sounding song.
• That One Level: Some of the "daredevil" challenges (red comets) fall into this category. A level that's easy to finish with plenty of power-ups scattered throughout can become an exercise in hair-pulling when you have to do it without taking a single hit or having a checkpoint.

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