AM2R (Another Metroid 2 Remake) is an action-adventure game developed by the Argentine programmer Milton Guasti (also known as DoctorM64) and released for Windows on August 6, 2016, Metroid's 30th anniversary.

AM2R is an unofficial remake of the 1991 Game Boy game Metroid II: Return of Samus by Nintendo, largely based on the visual style of Metroid: Zero Mission (2004). As in the original Metroid II, players control the bounty hunter Samus Aran, who aims to eradicate the parasitic Metroids. AM2R adds features including new graphics and music, new areas and bosses, altered controls, and a map system.

AM2R received positive reviews, particularly for its graphics. It was nominated for the Game Awards 2016, but was dropped from the nominee list without notice. Shortly after release, Nintendo sent D.M.C.A. notices to websites hosting AM2R, and download links were removed. Though Guasti planned to continue working on the game privately, in September 2016, he ended development after receiving a D.M.C.A. take-down request. Nintendo released an official Metroid II remake, Metroid: Samus Returns, in 2017.

AM2R is an enhanced remake of the Game Boy game Metroid II: Return of Samus, which follows Samus Aran on her quest to eradicate the parasitic Metroid species from SR388, their home world. The remake builds upon the visual style of Metroid: Zero Mission, adding a map system, new areas, mini-bosses, upgrades originally introduced in Super Metroid, redone graphics and music, an updated artificial intelligence for enemies, and a log system similar to Metroid Prime. Logs give the player more information on Metroids, enemies and the game world after the player has encountered certain enemies or arrived in new areas. The controls are less "floaty" than those of the original and feature new abilities such as wall jumping and grabbing onto ledges, more in line with the gameplay the series has employed since Super Metroid.

The Metroids the player fights have four main evolutionary stages – Alpha, Gamma, Zeta, and Omega – which have been altered compared to their Metroid II counterparts, including new techniques used in battle; Alpha is the least altered, having only been given a new dodge move, while Omega has been altered the most, having been changed to earth-bound enemies that trap the player. The player confronts these Metroid bosses often and has to defeat 55 of them. Among the newly added bosses are non-Metroid enemies such as a moving statue or a Torizo statue.

AM2R was developed by Milton Guasti under the pseudonym DoctorM64 over about ten years, with several breaks. Guasti wanted to recreate the fast gameplay of Metroid: Zero Mission and the "atmosphere and solitude" of Super Metroid. After finishing Metroid II for the first time, he imagined the game with modern gameplay, an in-game mini-map rather than a physical map, and the Omega Metroids as tall as the screen. As Guasti was not a programmer at the time, he used a trial-and-error method to modify a platforming game engine by Martin Piecyk within the game creation system GameMaker, with learning being his main motivation.

At first the remake followed the original Metroid II's map layout and existing sprites from Metroid: Zero Mission and Super Metroid. As Guasti kept working on the game engine and developed his skills, he felt that AM2R felt more and more authentic. After he announced the game, several artists volunteered to create original art; the Metroid evolutions were redesigned, and new enemies and areas unrelated to other Metroid games were added. Guasti remade the music while waiting for customers in his recording studio. The log system was designed to deliver narrative in a non-intrusive way.

Because so much was changed in AM2R compared to the original Metroid II – with color, a larger screen, "less claustrophobic" caves, and new gameplay controls – Guasti was faced with the challenge of recreating the original's feeling of danger within a more modern style. Metroid II featured "tight-quarters combat", while AM2R's greater amount of screen space and mobility meant that the Metroids' behavior had to be changed. They were made more agile and aggressive, with the intent that players would have to use all tools available to them to defeat them. The scale of the rooms throughout the game world also had to be changed, with some landmarks being redesigned to make better use of the larger screen; some, however, were kept similar in size to their Metroid II counterparts. While the game's first areas were made colorful and accurate to their counterparts in Metroid II, later areas were expanded and introduced new elements, featuring progressively darker caves, tighter passages, and Metroids found in more dangerous locations. This, along with increasingly darker and menacing music, was to recreate the feeling of Metroid II, which Guasti described as "being lost in a dark, mysterious cave without knowing what's ahead".