From the Super Mario Wiki
as it appears in Super Smash Bros. Melee
Octoroks are purple octopus-like enemies from the Legend of Zelda series. They appear in Super Smash Bros. Melee as enemies in the Underground Maze in Adventure Mode, taking their appearance from The Legend of Zelda: Ocarina of Time. They attack by spitting rocks at the fighters. They also appear during Versus Mode hidden in carrier items along with ReDeads, Goombas, and other creatures found in Adventure Mode, although this occurrence is rare. Octoroks return as enemies in the Smash Run gamemode of Super Smash Bros. for Nintendo 3DS. They take their appearance from The Legend of Zelda: Skyward Sword.
An Octorok (left) in Super Smash Bros. for Nintendo 3DS
Being one of the Zelda series' staple enemies, some Mario enemies have been based off of Octoroks. This includes Octolots and Octovaders from Super Mario RPG: Legend of the Seven Stars, Chuckoroks from Mario & Luigi: Superstar Saga, Squiglets, Squigs, Squogs, Squoinkers, and Dark Squiglets from Super Paper Mario, and King Kaliente and some Octoomba variants from Super Mario Galaxy and its sequel.
They make cameo appearances in The Legend of Zelda microgame from WarioWare: Twisted!, where they shoot at Link.
Super Smash Bros. Melee
||The Legend of Zelda
|These common enemies made their debut in the very first Legend of Zelda game and have been a staple of every game in the series since. They shoot rocks from their mouths at high velocity, but the projectiles are simple to block and do very little damage. Octoroks have low stamina, so they don't pose much of a threat to good fighters.
Super Smash Bros. for Nintendo 3DS
||This monster looks kinda like an octopus, but it shoots rocks out of its mouth. They've been around since the very first Legend of Zelda game, and the Octorok from Skyward Sword appears in this version of Smash Bros. They'll hide underground, emerging to fire at nearby fighters. If you're quick, you can run forward and pluck them out.
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