- Blooper: The Bonus Boss has an attack where, for one frame, they have leftover debug graphics and an extra floating hand next to their own hand.
- Development Hell: The unique 2D sprites that greatly resemble 3D models in a 3D world is what caused this game to have a long development cycle (that started right after the third game was released, no less). It got even longer when trying to avert a serious case of Ambidextrous Sprite for the bros.
- Executive Meddling: Subverted; the Iwata Asks reveals Nintendo made numerous suggestions to AlphaDream similar to Paper Mario: Sticker Star. However, AlphaDream did not accept many of the changes, often leading both parties to get annoyed at one another.
- Fan Nickname:
- Giant Giant Bowser, of course, for the result of an already-giant Bowser getting a second size boost at the end of his battle.
- Alternatively, Tera Bowser, to reference the final event in Super Smash Bros. Melee where you fought Giga Bowser, Ganondorf, and Mewtwo, and Giga Bowser could possibly grab a random Super Mushroom to increase his size even further.
- Milestone Celebration: This game was released as part of the Nintendo-declared "Year of Luigi", celebrating the 30th anniversary of Luigi's debut in Mario Bros.. In an unintentional example, the game is this for the Mario & Luigi series, as this game was released in 2013, ten years after Mario & Luigi: Superstar Saga was released.
- Name's the Same: Before you ask, it's Luigi, not Nail that gets nicknamed "Big Green" by the Dreamy Stone Spirit.
- What Could Have Been: The giant battles were originally supposed to feature the same Sprite/Polygon Mix as the rest of the game. But the team found that this wouldn't mesh too well with the new mechanics they wanted to add, requiring them to hand them over to a separate company to finish up.
- Why Fandom Can't Have Nice Things: Because of a bug in the original version of the game, people could post any saved image from the Nintendo 3DS Camera or the Internet Browser to the Mario & Luigi: Dream Team community. Naturally, everyone started abusing it, leading to the ability to post screenshots in the game's Miiverse community to be revoked on September 15, 2014. The ability was eventually restored, but only after a mandatory update patching the exploit.
Trivia / Mario & Luigi: Dream Team