Young Link

Young Link is a main character of the Legend of Zelda series. He could almost be considered to be the main character, as he is actually the younger form of the franchise leader, Link. He is shown to be quite skilled with a short sword, as well as many other weapons.

Super Smash Bros Series
Mario crossed paths with Young Link in Super Smash Bros. Melee. Here he was an unlockable character, unlocked by beating Classic or Adventure Mode with 10 characters, and then beating him. He is shown to have a fighting style similar to Link's (which makes him a clone of Link), but he is weaker and cannot throw Bombs as far. His sword is also shorter, and his Boomerang cannot be thrown as far. However, he is much faster than his older self, and has better control over his Boomerang. Like his older self, Young Link can use a variety of weapons, including Arrows, a Boomerang, and a Deku Shield. He is also able to perform the Wall Jump, which the adult Link is not able to do. Young Link was voiced by the female voice actress, Fujiko Takimoto.

It's unknown if he'll return in the sequel Super Smash Bros. Brawl.

Young Link has a unique and humorous Taunt where, instead of showing-off or mocking his opponent, will just pull out a bottle of Lon Lon Milk, and drink it all. Lon Lon Milk is one of the best drinks in The Legend of Zelda: Ocarina of Time. This taunt is also the longest taunt in Super Smash Bros. Melee.

Classic
''Link's younger incarnation is often considered to be the true Link: he was a young boy in the very first Legend of Zelda game, and he has appeared as a youth in most of the subsequent games. Since his debut on the original NES in 1987, Link's appearance has changed over and over again, each time adding to the mystique of his incomparable story.''

Adventure
''Young Link is lighter and faster than his older self, and his Kokiri sword packs less punch. Even though his Boomerang has a shorter range, he has greater control over it. He's a smaller target, and while his Hookshot has less reach than older Link's, you can still use it in midair as a last ditch attempt to grab a ledge.''

All-Star
''With a youthful spring in his step, Young Link can perform amazing wall-jumps. Once he hits a wall, tap the Control stick in the opposite direction to send him leaping upward; you can practice to your heart's content in Target Test. His Spin Attack can strike multiple times even on the ground, and although it's hard to discern, so do his Bombs.''

Trivia

 * Young Link appears in a microgame in Wario Ware: Smooth Moves, where he has to pull the Master Sword out by using the janitor technique and will transform into either the current Link, an old version of Link, or a chicken.
 * The costume changes Young Link were said to be different tunics with unique powers. This was later proven false.