Pikmin

Pikmin are a plant-animal hybrid species and the namesake of the video game series, Pikmin. They have cameoed in Mario games twice thus far, but their main role is in Super Smash Bros. Brawl, where they are assistants to Captain Olimar.

Mario Golf: Toadstool Tour
The Pikmin's first appearance in the Mario series was in Mario Golf: Toadstool Tour. Here, if the golf ball landed in a patch of flowers, Pikmin would pop out. This implies that Pikmin may live in the Mushroom World, in addition to Earth.

Super Smash Bros. Brawl
Pikmin serve Captain Olimar in Super Smash Bros. Brawl. Although they are technically not playable, Olimar is almost completely helpless without them, for they are featured in all of Olimar's Special Moves. As such, they must be plucked from the ground. When Kirby gets Olimar's ability, he can also use Pikmin, but after plucking them, he immediately throws them.

The Subspace Emissary
Captain Olimar's Pikmin are attacking a huge R.O.B., however, they are so weak they do no damage. The R.O.B. simply spins around and all the Pikmin that were on him fly in all directions and turn into ghosts and die. Captain Olimar starts shivering in fear at the huge robot. A red Pikmin walks up to Olimar and taps him on the side. Olimar turns around and the red Pikmin points out the Blue Falcon speeding through the forest.

Captain Falcon jumps out of the Blue Falcon and then Falcon Punches the huge Robot right in his face. The R.O.B. then falls back destroyed. Captain Falcon lands back on the ground while doing a slide similar to the Falcon Kick. However, while he is sliding on the ground, he accidentally hurts Pikmin that came in contact with him and killed them all. Captain Falcon just stands there striking a pose while Captain Olimar and the red Pikmin watch as the wind blows a leaf by. Olimar and his Pikmin decide to team up with Falcon.

WarioWare: Smooth Moves
Pikmin later appeared in a Pikmin 2 microgame in WarioWare: Smooth Moves, which belonged to 9-Volt. Here, the player controls Empress Bulblax and must roll over all of the Pikmin to squish them before the time runs out. However, it will get harder. The Pikmin will grow larger and start jumping over the player.