Goldeen

Goldeen (, Tosakinto in Japanese language versions) is a fictional creature in the Pokémon media franchise.

This is a Poké Ball Pokémon that appears in all three Smash Bros. games, which is a rarity because the only other known such Pokémon are Electrode*, Mew and Snorlax (although Charizard also appears in all three, it makes its debut as a playable character in Brawl instead of coming out of Poké Balls).
 * Electrode doesn't appear from a Poké Ball in SSB, but rather as a stage hazard in Saffron City.

Creature description
Goldeen has the appearance of a goldfish. The top of its body is reddish-orange while the lower half is all white. It has red lips that resemble the lips of a female human being, and a horn on its head that can perform attacks in the Pokémon games.

The role Goldeen plays in the Smash Bros. series should not be confused with its role in the Pokémon games; there, it possesses more attacks. The Pokémon Magikarp would match Goldeen's role in the Smash games perfectly, as it can only use Splash for quite some time. Goldeen can't even learn "Splash."

Goldeen's inability to do anything other than flop around seems to be a reference to the second episode of the Pokémon television series, where Misty summons a Goldeen in a battle with Team Rocket, only to have it flop around due to the lack of water.

As a Poké Ball Pokémon
Goldeen appears as a Poké Ball Pokémon in Super Smash Bros.. It flops around on the stage helplessly until it disappears or has fallen off the stage. It is one of four completely harmless Pokémon in series game, the others being Mew, Jirachi, and Celebi. Goldeen does not have any hitboxes; none of its attacks give damage to any of the characters. Thus, it is established as the "dud" Pokémon of the Smash Bros. series.

As a Poké Ball Pokémon
Goldeen returns in Super Smash Bros. Melee to reprise its role exactly as something that does not affect gameplay in any way.

Starting here, rumors have flown around the Internet claiming that under certain conditions, Goldeen will activate Horn Drill and instantly KO an opponent. Although this has never been completely proven or disproven, most people accept it as false, due to a lack of evidence beyond a glancing mention in the Melee trophy. Surprisingly, Goldeen does nothing special on stages with water.

As a stage element
A larger balloon of Goldeen (in actuality the 3D model of Goldeen used in Pokémon Stadium for Nintendo 64) is one of the many floating and bending "platforms" that comprise the Poké Floats stage.

As a trophy
Goldeen features as a collectible trophy, unlocked as one of the 100+ trophies that can be collected randomly during normal play, such as in the Trophy Lottery and throughout the various Single-player Regular Matches. It reads as follows:

''A Goldfish Pokémon. In contrast to its elegant appearance, it has a wild temperament, and its attack with its horn is severe. Among the techniques it can master, Horn Drill is especially reliable. It evolves into Seaking, but if it's raised without evolving, it can learn the powerful Bug-type move Megahorn. There are male and female Goldeen--the male's horn is longer.''

As a Poké Ball Pokémon
Goldeen returns in Super Smash Bros. Brawl and, you guessed it, it's just as useless as before. The description on the Dojo tells the player to watch out for Murphy's Law (whatever can go wrong will) when using Poké Balls, showing Goldeen's picture.