Originally the development team consider using Bowser's car from Super Mario 3D World for Mario to drive around in the Super Mario 3D World style, but they instead decided to go with the Koopa Troopa car because of how difficult it would've been to replicate Bowser's car in Super Mario Maker 2.

In Konquest Mode, remaining idle on dialogue screens at certain points will cause a monk towards the bottom of the screen to break the fourth wall; turning around to look at the player and shrugging before resuming his original position.

There were two factors that prevented Seiken Densetsu 3 from being localized back in the mid 1990s. According to former Squaresoft employer Fehdrau, the first was that there were glitches in the Japanese version that wouldn't be able to pass Nintendo of America's certification process. According to Retro Gamer Magazine, the second one was that there was a lot of text. Squaresoft (now Square Enix) declared that fixing these issues for a localization would be too costly on a system that late in its life cycle.

Sometime in December 2015, a 28-year old male Russian sued Bethesda Softworks and its localization studio because the game ruined his life. He claimed he was so addicted to the game, it caused his wife to leave him and led to him being fired from his job.

In the Misty Stream area of the game, the player can find a wreckage of a pirate ship which appears to be the Phantom Storm boss from Kingdom Hearts 2, as can be seen by the identical jaw piece.

There is an unused race within the game's data called "Ghost". It has 50 health and is immune to suffocation damage. It's rumored that these were originally part of a scrapped event but they can be re-enabled by editing some of the game's files.

In an Sega.jp Meisaku interview with game's creator Kotaru Hayashida (aka Ossale Kohta), he stated that the 'Octopus Sushi' was originally going to have at least 8 arms. But it was impossible, due to an issue with the sprites.

In Japan, the game has been renamed to 'Mortal Kombat: Legends of the Advent God Fist'.

In Japan, the game was renamed to 'Mortal Kombat II: Ultimate Godly Fist'.

In the prototype version of this game, a 3D model of the Titus fox was used as opposed to a 2D one seen in the final release.

Part of the newly implemented Athletic Theme that plays during sky levels in the Super Mario Bros. style plays a portion of the results theme from the arcade game VS. Super Mario Bros..

An unused CD graphic exists in the game's files. It is theorised that this belongs to an unused song, "Addicted To Bass", since there is a reference to it in the files.

Within the PlayStation version of this game are unused pictures from the demo version of Croc 2, another one of Argonaut Software's games.

In the Arcade version's Attract Mode, Rain can be seen fighting Shao Khan for about a second. Rain was not a playable character in this version but was added to stir up rumors of his alleged inclusion.

Upon closer inspection it can be noted that Rain's name within his health bar is copy-pasted in a different font than what is standard for character names during matches.

According to producer Katsuhiro Harada, SEGA offered a free Virtua Fighter character to be added into the game if the game was ported to the Dreamcast.

In February 2015, Warner Bros was given a small window of permission from Todd McFarlane to use Spawn in its games. However, Ed Boon was unaware of the offer two months later, despite revealing that Spawn was discussed as a potential guest character. Spawn would later be added in Mortal Kombat 11.

Files for Dragonite from the Pokémon series suggest it may have been planned to be summoned from the Poké Ball. While it does not appear as an assist character in the final game, it does appear as a background character in the Kalos Pokémon League stage. Two models for the character exist, with one more in line of those summoned by the player, featuring higher resolution textures.

The Insane Cults offense player Vitas Varnas is a reference to the real-life actor, producer and writer of the same name.

On July 17th, 2019, as part of a promotion with Nintendo, Southwest Airlines gave everyone on a flight heading to San Diego for San Diego Comic-Con a free Nintendo Switch bundled together with Super Mario Maker 2.

In the fifth mission of the bonus mode Half-Life: Decay in the PlayStation 2 port of Half-Life, the corpse of a guard can be found floating in a pool. The corpse has over 3,000 health and if hit enough times, it will destroy and spawn Snarks which can be acquired for use.