* AnticlimaxBoss: As if to throw the player a bone for the game's infuriating difficulty, the Bowser fights are unchanged from the first game. 8-4 adds two Bowsers to the mix, but you can skip the first one, and the game gives you at least two chances to get a secret mushroom/fire flower beforehand (if you can find them and keep them). Just watch out for the warp pipe pit with Invisible blocks and the lava pit/pirahna plant combo (plus a lone buzzy beetle) preceding the real Bowser.
** 3-2 and 6-2, the two main underwater levels, are tricky, but relatively easy compared to the rest of the game.
** After the insanely grueling 7-2, the game treats you to 7-3, one of the easier levels in the game, which has very few enemies and only consists of super springs and reasonably big platforms, with just enough time for you to figure out where to land. It's tricky, but not hair pulling in difficulty. The same cannot be said for its [[HardModeFiller later equivalent]], C-3, which adds a single [[DemonicSpider Lakitu]] just to make your life miserable.
** B-4. Compared to the extremely difficult B-3 (or, really, any other level in the game), this level is a cakewalk. The bulk of the level is a repeating section where you get past an easy to dodge fire bar and pipe. No maze or anything else that's particularly difficult. Probably the easiest castle in the game.
* ContestedSequel: Fans either like this game for being an enhanced version of the original with unique and more difficult levels, or dislike it because it's [[ItsHardSoItSucks too difficult]] and [[MissionPackSequel doesn't really change much]].
* CultClassic: Due to its insane difficulty and similarity to the original ''Super Mario Bros.'', it doesn't get as much universal love as the other games in the series. Those who do love it, however, love it for exactly the reasons listed prior.
* DemonicSpiders: The Hammer Brothers in the original game were hard enough, but this one adds a variant that continually marches up towards the player. This version is even more difficult to pass without taking damage.
* ItsHardSoItSucks: Part of why the game wasn't exported, and why it had poor reception amongst Western players after it was RemadeForTheExport. Even [[OldShame Miyamoto himself disliked the]] SequelDifficultySpike. The other reason is that...
* ItsTheSameNowItSucks: Wasn't just a fan reaction. The #1 reason Nintendo decided not to export the Famicom version to the US was that they didn't think such an obvious MissionPackSequel would sell well in the States (note that simply being NintendoHard didn't stop them from exporting any other games back then).
* MostAnnoyingSound: Tired of the classic death jingle from playing the original ''Super Mario Bros.'' yet? If not, [[NintendoHard you will be long before you hit World 8]].
* PainfulRhyme: The poem you get after beating 8-4, which also appears in ''Vs. Super Mario Bros.'':
-->Peace is paved/With kingdom saved/Hurrah to Mario[[note]]or Luigi, but that breaks the rhyme[[/note]]/Our only hero/This ends your trip/Of a long friendship[[note]]100000 pts. added/For each player left.[[/note]]
* PortingDisaster: The GBC port on ''Super Mario Bros. Deluxe'' isn't necessary unplayable, but it strips several features from the original, which is not brought up in-game or in the manual. Luigi as presented in the original is not available (you can switch between him and Mario on the world map, but he's merely a PaletteSwap in this version), worlds 9 through D are absent, the game uses Super Mario Bros. 1's physics (no [[GoombaSpringboard high bounce out of enemies]]) and graphics, the wind mechanic is removed, and [[CameraScrew the smaller screen introduces some serious]] FakeDifficulty.
** If you use a Warp Zone before hitting World 9, [[LostForever World 9 is gone for good]]. Fair enough, the point is that World 9 is a reward for determined players. But if you play the ''All-Stars'' version, which has saving, reach World 9, then later use a Warp Zone, you will lose the World 9 privileges that you were previously rewarded with for your current save file. Forgetful players may then choose Save & Continue or Save & Quit rather than resetting or powering off the console and then find themselves having to unlock World 9 ''again from scratch.''
** Do you want the four extra worlds and the true ending in the original version? You have to beat the game ''[[FakeLongevity eight times, with no Warp Zones]], and [[SaveGameLimits no powering the system off]]!'' No wonder the ''All-Stars'' remake loosens the condition to "just beat the game once"!
* SophomoreSlump: Even among the players who were baffled at the Western version of ''Super Mario Bros. 2'' (for being a DolledUpInstallment of ''Doki Doki Panic''), few will consider this game to be a much better alternative. It being an encore of the original ''Super Mario Bros.'', the extreme difficulty and the need to beat it multiple times to unlock all of the levels means that the game was never meant to progress the original formula.
* ThatOneLevel: Everyone probably has their own opinion of which levels are the most difficult. But, for a specific example, [[TheAngryVideoGameNerd Mike Matei]] did a live stream of the game in November 2015. It took him ''several hours'' to sucessfully get through level 8-3 (which has an abundance of Lakitus, Hammer Bros., and near-impossible platform jumps). [[ThisIsGonnaSuck And, he knew ahead of time that 8-4 was gonna be a bitch.]]