History YMMV / SuperMarioGalaxy

* TheyWastedAPerfectlyGoodPlot: The spaceship that Bowser uses to rip Peach's Castle out of the ground using lasers would've made for an epic boss. Too bad it only appears in cutscenes and never during gameplay.

** Then there's Luigi himself, whose missions involve him getting stuck when finding a star in familiar territory. He does this a grand total of three times before being burned out, all of which are in early stages. Needless to say it would have been interesting to see him do some searching in a plethora of later galaxies, [[AuthorsSavingThrow which the sequel thankfully implements by making him a late-game unlockable alternate character who can swap out with Mario]].

* UnintentionallySympathetic: Because you have to advance through the game, the player has to forcibly hatch Dino Piranha from its egg. Despite it being a giant monster, some players feel bad for killing a new-born baby that they themselves hatched. It being UglyCute probably helps.

** The Luma who travels with Mario and grants him the new spin ability never gets any dialogue after joining Mario, acting more as an object rather than a genuine companion. Contrast this to F.L.U.D.D. from the previous game who granted the gimmick and talked to Mario throughout the adventure. Had the Luma been given more personality and talked throughout the adventure, it would've made his sacrifice at the end all the more emotional.

* TheyWastedAPerfectlyGoodCharacter: After Kamek blasts Mario into space in the opening, we never see him again, with Kamella taking the boss role (and not much of a story role past that) and all other Magikoopas being the basic enemies.

*** Purple Coins in the Bone Pen, mostly because you're only given ''a mere minute'' to complete this mission. There are 150 purple coins[[note]]one of the coins is on the backside of the starting planet, but it's almost never worth trying to go for due to the time it takes to get it[[/note]] in a small area with pull stars, mines, and meaty bones, and the player will need to use the pull stars to get at least 100 of them. The pull stars can be tough to control, especially when combined with the strict time limit, the meaty bones will throw you off course if you touch them, and the mines can quickly spell your demise if you hit too many of them. And worst of all, once you collect the 100th coin, the timer doesn't stop counting down, which can result in a very frustrating death right as you were about to get the star.

** [[PowerupLetdown The Spring Mushroom power-up.]] You can't stand still while you're wearing it, the movement is very wobbly, and it requires precise timing in order to do a high jump (and unsurprisingly, the areas in which you find the spring require many such jumps). It doesn't help that it doesn't debut until Toy Time Galaxy (very late in the game), which means you have to use it on some of the harder levels without having a chance to practice using it in easier levels first. It even appears to be this in-universe, as [[http://www.mariowiki.com/File:Spring_Mario_Art_-_Super_Mario_Galaxy.png the promotional picture]] of this power-up shows Mario looking horrified as if to say [[WesternAnimation/TheJetsons "STOP THIS CRAZY THING!!!"]] Fortunately, it only appears in four missions (two missions in Toy Time, the only mission in Matter Splatter, and Beach Bowl's purple coin mission).

** The Undergrunt Gunner rematch in Toy Time Galaxy all but requires you to use the [[ScrappyMechanic Spring Shroom]] just to jump up to damage him, which combined with him shooting balls of electricity and the arena being over a bottomless pit can make the fight agonizing, especially if you haven't mastered the Spring Shroom by now.

*** Purple Coins in the Desert, due to the instant-death [[QuicksandSucks quicksand]] and the hard-to-control tornado-powered gliding required to reach many of the purple coins (often above the quicksand). Some ''very'' precise timing is needed as well with the tornadoes to even get high enough to reach those coins.

** Beating the game while collecting as little star bits as possible. Since nearly everything in the game drops star bits, careful platforming and movement of the pointer is required to avoid picking them up. [[spoiler: Unfortunately, it's impossible to beat the game with ''zero'' star bits, as you are required to pick them up to complete a tutorial at the beginning of the game, and Good Egg Galaxy's second mission (where you need to collect 100 star bits to feed a hungry luma) is required, as no other level is available at that point.

** When Bowser's vulnerable to attack, [[MusicalSpoiler the player will hear chanting]]. Naturally, many players mishear this as "SOAP SOAP, POPCORN, OH POPCORN! THUMP THUMP THUMP THUMP"

** Luigi's Purple Coins is infamous among the purple coin levels. The good? There are 150 purple coins, and you don't have to collect them all. The bad? The level consists entirely of platforms that either start slowly rotating or disappearing when you step on them, and the rest consists of instant-kill sludge. The more of the level you walk on, the less safe ground you're left with, especially considering the fact you have to return to the starting point once you're done, so you have to remember to leave some walkable ground for the return journey. Oh, and you only have three minutes to complete the whole thing.

* BreakoutCharacter: Rosalina graduated from EnsembleDarkhorse to this, appearing quickly in spinoffs like the ''VideoGame/MarioKart'', ''VideoGame/MarioParty'', ''VideoGame/MarioTennis'', and ''VideoGame/MarioGolf'' subseries, being PromotedToPlayable in ''VideoGame/SuperMario3DWorld'', and being featured as a fighter in the ''VideoGame/SuperSmashBros'' series.

* BreakoutCharacter: Rosalina graduated from EnsembleDarkhorse to this, appearing quickly in spinoffs like the ''VideoGame/MarioKart'', ''VideoGame/MarioTennis'', and ''VideoGame/MarioGolf'' subseries, being PromotedToPlayable in ''VideoGame/SuperMario3DWorld'', and being featured as a fighter in the ''VideoGame/SuperSmashBros'' series.

* EpilepticTrees: Rosalina has been an endless fountain of speculation over the years regarding her nature and her origins. About the former, a very common theory is that she's the creator of the Mario universe, [[https://www.youtube.com/watch?v=9iNs5iG2h34&feature=player_detailpage#t=436 and its literal God(dess)]]. About the latter, her uncanny, albeit so far unexplained resemblance to Peach makes everyone assume they're both related one way or another. From people who believe she's her lost sister or her future daughter, as well as Mario's... [[https://www.youtube.com/watch?v=xzWFuEH9HsA or Luigi's.]]

* BrokenBase: The addition of Rosalina's storybook as a whole. Some found it to be a deeply compelling (for ''Mario'' standards anyway) and emotional backstory that serves to make Rosalina all the more interesting, while others (including Creator/ShigeruMiyamoto [[CreatorBacklash himself]]) felt it was an unnecessary addition whose dramatic tone is unfitting for a ''Super Mario'' game and is too much of a MoodWhiplash with the game's otherwise lighthearted and fun tone (regardless of if it's optional or not)? Given the nature of this debate, it tends to frequently boil over into the wider debate on how much should story play a role in the ''Mario'' series, if it should at all.

* BrokenBase: The addition of Rosalina's storybook as a whole. Some found it to be a deeply compelling (for ''Mario'' standards anyway) and emotional backstory that serves to make Rosalina all the more interesting, while others (including Creator/ShigeruMiyamoto [[CreatorBacklash himself]]) felt it was an unnecessary addition whose dramatic tone is unfitting for a ''Super Mario'' game and is too much of a MoodWhiplash with the game's otherwise lighthearted and fun tone (regardless of if its optional or not)? Given the nature of this debate, it tends to frequently boil over into the wider debate on how much should story play a role in the ''Mario'' series, if it should at all.

* BrokenBase: The addition of Rosalina's storybook as a whole. Some found it to be a deeply compelling (for ''Mario'' standards anyway) and emotional backstory that serves to make Rosalina all the more interesting, while others (including Creator/ShigueruMiyamoto [[CreatorBacklash himself]]) felt it was an unnecessary addition whose dramatic tone is unfitting for a ''Super Mario'' game and is too much of a MoodWhiplash with the game's otherwise lighthearted and fun tone (regardless of if its optional or not)? Given the nature of this debate, it tends to frequently boil over into the wider debate on how much should story play a role in the ''Mario'' series, if it should at all.

* BrokenBase: The addition of Rosalina's storybook as a whole. Is it a deeply compelling (for ''Mario'' standards anyway) and emotional backstory that makes Rosalina all the more interesting, or is it an unnecessary addition that is too much of a [[MoodWhiplash jarring clash]] with the game's otherwise lighthearted nature. The fact that the storybook is purely optional does not do much to alienate the debates. Notably, Miyamoto was firmly in the [[CreatorBacklash latter group]], seeing as he made the devs scrap their story related plans for ''VideoGame/SuperMarioGalaxy2'' (which ended up being a divisive move in its own right). Given the nature of such debates, many of these debates tend to boil over into the greater debate on how much should story play a role in the ''Mario'' series, if it should at all.

* BrokenBase: The addition of Rosalina's storybook as a whole. Is it a deeply compelling (for ''Mario'' standards anyway) and emotional backstory that makes Rosalina all the more interesting, or is it an unnecessary addition that is too much of a [[MoodWhiplash jarring clash]] with the game's otherwise lighthearted nature. The fact that the storybook is purely optional does not do much to alienate the debates. Notably, Miyamoto was firmly in the [[CreatorBacklash latter group]], seeing as he made the devs scrap their story related plans for ''VideoGame/SuperMarioGalaxy2'' (which ended up being a divisive move in its own right). Given the nature of such debates, many of these debates tend to be boil over into the greater debate on how much should story play a (if any) role in the ''Mario'' series.

* BrokenBase: The addition of Rosalina's storybook as a whole. Is it a deeply compelling (for ''Mario'' standards anyway) and emotional backstory that makes Rosalina all the more interesting, or is it an unnecessary addition that is too much of a [[MoodWhiplash jarring clash]] with the game's otherwise lighthearted nature. The fact that the storybook is purely optional does not do much to alienate it. Notably, Miyamoto was firmly in the latter group, seeing as he made the devs scrap their story related plans for ''VideoGame/SuperMarioGalaxy2'' (which ended up being a divisive move in its own right).

* BrokenBase: The addition of Rosalina's storybook as a whole. Is it a deeply compelling (for ''Mario'' standards anyway) and emotional backstory that makes Rosalina all the more interesting, or is it over-dramatic {{Narm}} that is too much of a [[MoodWhiplash jarring clash]] with the game's otherwise lighthearted nature.

* EvilIsCool: After his goofy outing in ''VideoGame/SuperMarioSunshine'', Bowser's coolness comes roaring back with a vengeance here, where he's a successful galactic conqueror whose boss fights are set to epic orchestrated music that wouldn't sound out of place in a ''Franchise/StarWars'' movie.