Super Mario World Edit
Super Mario World (SNES) is a traditional platforming game, in which Mario must rescue the princess from Bowser (for only about the third time). Super Mario World is the flagship game among SNES games.
ROM hackers, who want to create custom Mario levels, often elect SMW as the base hack. SMW has more hacks than any other Mario game. SMW hackers have built new levels from blocks and replaced the graphics. Assembly hacking of SMW has introduced new blocks and sprites.
SMW hackers prefer Super Mario World (U). There exist hundreds of SMW hacks; practically all of them are hacks of the American SMW.
SMWcentral is the main resource for SMW hacks, for both players and hackers.