Though Nintendo recently updated Super Smash Bros. 3DS to version 1.0.3, the House of Mario has announced that a new balance patch, 1.0.4, will soon be available.
Details on what exactly the patch might change are scant. Nintendo's in-game notice to Super Smash Bros. 3DS players states simply, "This patch will adjust the game balance by refining the strengths of some fighters. It also includes various other gameplay fixes." The notice then goes on to warn players that Super Smash Bros. 3DS 1.0.4 is incompatible with older versions of the game, and that installing the patch will "disable playback of replays saved using older versions."
There is no solid release date for the free update, though Nintendo is "planning to release the patch within the next month." As with all Super Smash Bros. 3DS updates, this patch is mandatory for anyone hoping to play online.