An Unira (ウニラ, unira) is an item that appears in Super Smash Bros. Brawl. It originates from a game called Clu Clu Land. It is a type of Sea Urchin encountered in said game, acting as an enemy. In Brawl, it appears that when thrown, it can extend its spikes and can be enlarged. It also has a subtle vacuum effect on nearby foes.
The Uniras made their first appearance in the game Clu Clu Land. In Clu Clu Land, Uniras are sea urchins that were stealing treasure from the underwater kingdom Clu Clu Land. Uniras also appear as on-screen enemies in Clu CLu Land. If the player touches a Unira, the player gets hurt. The player can defeat Uniras by sending out sound waves to stun them, and then smash them into a wall. In Brawl, Uniras appear as an item that can be picked up and thrown. When the Unira lands on the ground, it sticks out it's spikes which are able to damage other players.
In Clu Clu Land, the Unira hid gold ingots in an underwater maze, then tried to stop Bubbles from getting them. In Super Smash Bros. Brawl, you can attack an Unira to send it bouncing away. Any fighter it hits will go sprawling. If it hits a wall, it'll bounce back, and if you hit it with a powerful attack, it will transfer the attack to whomever it hits and launch them.