Meta Knight

Meta Knight is one of Kirby's rivals and sometimes friend. Meta Knight was born in Dream Land, where Kirby also grew up in. As such, he loves his home, and will do anything to make it a better place. Unfortunately, his ways sometimes involve violence (like trying to create a war with Dream Land to cure them of their laziness), and he will not hesitate to hurt even Kirby, to get what he wants. Despite this, he is actually a mis-understood villian. He is also the only other one of Kirby's (unknown) species, only further tying the two together.

Super Smash Bros. Series
Although he didn't appear playable, Meta Knight had a trophy dedicated to him in Super Smash Bros. Melee. It was randomly won through Grab the Trophy on Classic Mode, or the Lottery.

However, Meta Knight will appear as a playable fighter in the upcoming Super Smash Bros. Brawl. His purple cloak will be able to transform into wings, just as his Trophy from Melee said. He will utilize his sword as his main weapon of choice. He can also multi-jump like Kirby and Jigglypuff and, by using his wings, he can float like Peach. He will also have a stage in his honor, his very own war ship called the Halberd. Interestingly, besides being one of Kirby's species, most of Meta Knight's attacks seen so far, are not clones of Kirby's attacks. This hhinted a possible end to the clones from Super Smash Bros. Melee.

Trophy Information from Super Smash Bros. Melee
''The mysterious head of the Meta-Knights, he wields his sword with dignity. He delivered his sword to Kirby and demanded single combat in a show of knightly honor; his strict adherence to his code of ethics makes him a rarity in Dream Land. Sometimes he throws off his cape in battle. It occasionally transforms into wings.''

Trivia

 * Meta Knight was also in Nintendo Monopoly, where he took the position of St. Charles Place, and costed $140.