Ness

Ness is the main protagonist of the cult classic game EarthBound. He is an adventurous 13-year old boy who tries to stop an alien invasion in EarthBound. Ness is a playable fighter in every Super Smash Bros. game.

Super Smash Bros.
In Super Smash Bros., Ness is one of the unlockable fighters, and he can be unlocked by clearing 1P Game on a Normal difficulty setting with at least 3 stock and no Continues. Once the task has been fulfilled, the player's fighter has to fight Ness and defeat him, therefore unlocking him.

Ness was also a bit of a surprise addition to the roster, as no one expected such an obscure character to appear in the game.

Super Smash Bros. Melee
In Super Smash Bros. Melee, Ness is instead one of the starting fighters. He keeps all his special moves and gains a fourth move (PK Flash) like every other veteran.

When Melee was in development, Ness was intended to be excluded and replaced by Lucas from Mother 3, which was being developed for the Nintendo 64 at the time, but due to the cancellation of Mother 3's original release on the Nintendo 64, Ness was added instead.

Super Smash Bros. Brawl
In Super Smash Bros. Brawl, Ness returns as a playable fighter, this time alongside another EarthBound fighter, Lucas. Ness is also an unlockable character, and he can be unlocked by playing The Subspace Emissary, reflecting 10 projectiles, or by playing 5 VS Matches.

Super Smash Bros. for Nintendo 3DS / Wii U
In Super Smash Bros. for Nintendo 3DS / Wii U, Ness returns as a playable character again. In Super Smash Bros. for Nintendo 3DS, Ness is an unlockable character, and he can be unlocked by playing 10 VS matches or by clearing Classic Mode. In Super Smash Bros. for Wii U, Ness is instead available from the start.

Strangely, Ness was announced for Super Smash Bros. for Nintendo 3DS / Wii U but Lucas was not. This led players to speculate that this was a similar case to Ness's appearance in Super Smash Bros. Melee, where Lucas was planned to replace Ness. This did not occur, and it was simply just a matter of Masahiro Sakurai selecting Ness over Lucas as the EarthBound representative. Lucas would later be announced as a DLC fighter.

Super Smash Bros. Ultimate
Ness returns with the rest of the fighters in Super Smash Bros. Ultimate as an unlockable character. He was announced on June 12, 2018. As the first character in Kirby's Classic Mode route, it is possible for Ness to be the first character unlocked in the game.

Trivia

 * Had Mother 3 not been delayed prior to Super Smash Bros. Melee's release, Ness would have been the only character from the first Super Smash Bros. to be removed from a later installment.
 * Ness would have also been the first character to be replaced by another character. He would be followed by Young Link, who was replaced by Toon Link in Super Smash Bros. Brawl.