An Unira (ウニラ, Unira) is an item that appears in Super Smash Bros. Brawl and Super Smash Bros. 4. 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. Additionally in Brawl, erected uniras will damage anyone except for the character who threw it, allowing them to stand behind it and crouch, providing adequate defense against others.
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 its 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.
What a cute little creature! You just want to... Oh, wait—those spikes aren't just for show! Once thrown or attacked, its spikes extend out and hurt anyone but the character who threw it. Attacking it again can make the spikes retract, so you could even throw it back at the original owner.
This blue ball's looks can be deceiving! When you throw or attack it, sharp spikes burst out and turn it into a real prickly nuisance! If you're the one who triggered it, though, don't worry - you're safe. With that in mind, stick it to a wall or ceiling in a narrow spot to really do some damage!