Fan games are unofficial games based on the Super Smash Bros. series, but created by fans with low or non-existent budgets. While they are unofficial, they are sometimes considered an important part of the Smash Bros. community. Multiple fan games have been created, each with their own fanbase. As a difference to retail products, fan games are free, and require a simple internet download. Fan games often add characters many fans want in the official Smash Bros. games, and are made with completely 2D sprites and backgrounds, compared to the 2.5D of the official Smash Bros. games. Many fan games also tend to have considerably simpler mechanics than retail games; Super Smash Flash, for instance, only gives roughly five moves to a character, while MultiHero characters have around seven.
While there are many popular fan games, among the most well known include Super Smash Flash (Which was horribly rated by fans), its sequel Super Smash Flash 2 (Which also failed) and Super Smash Bros. Crusade. Numerous other exist, such as Super Smash Bros. NES, Super Smash X, Super Nuke Bros., and MultiHero.
Fan games, however, can have their own properties. MultiHero, for instance, has the concept of "Super Specials", which predated the concept of Final Smashes in Brawl.