Super Mario Bros 2 (Nintendo NES, 1988)

For the U.S. sequel to Super Mario Bros., Nintendo retrofitted an Arabian-themed Japanese game called Yumekojo Doki Doki Panic with the familiar Mario clan. Other than a few minor graphical changes, the two games are nearly identical. 

With the Mushroom Kingdom safe for the time being, Mario and his crew seek out new adventures in Sub-Con, a dream world taken over by the demented Wart. This sequel is missing the two-player feature of the original but adds the ability to choose from four playable characters at the beginning of each level: Mario, Luigi, the Princess, and Toadstool. The game is made up of seven words divided into 20 levels, and the end of each world contains a boss that must be defeated before proceeding. 

An entirely new cast of enemies is introduced, including Shy-Guys, Snifits, and Bomb-ombs, and most of the power-ups from the first game are missing or have different uses. Mushrooms function as extra lives, and coins are used to play the bonus slot-machine game at the end of each level. Each character now has a life meter that can be refilled by hearts (which also make the characters "big").

Rather than jumping on enemies to defeat them, Super Mario Bros. 2's primary attack method involves picking up items and throwing them. Vegetables can be plucked from the grass and thrown, but other enemies will also work. In certain areas, a magic potion will emerge from the grass instead of a vegetable, and this potion can be used to temporarily enter Sub-space, an area that often contains a mushroom or heart, and where the grass reveals coins.

Each playable character has a complex interaction between their speed, strength, and jumping ability. To put it simply, Mario is average in each category, Luigi can jump the highest, the Princess can float but is otherwise weak, and Toad can't jump well but is the strongest.

Although it was originally based on a non-Mario game, many of the items, enemies, and gameplay concepts introduced in Super Mario Bros. 2 went on to play an integral role in future Mario adventures. The game was re-released as part of Super Mario All-Stars for the Super NES in 1993, and in Japan as Super Mario USA in 1992.