Hero

Hero commonly refers to Agent 3 or Agent 4, the protagonist respectively in and  single-player mode, Octo Valley and  Octo Canyon. It may also refer to Octo Valley or Octo Canyon itself, also known as Hero Mode in the Japanese version.

Or of the suits worn by Cap'n Cuttlefish's agents. Or the Replica gear based off these suits.
 * Hero Suit
 * Armor

Or the Main Weapons used in Octo Valley and Octo Canyon.

Or the Replica weapons based off of them.
 * Hero Shot
 * Hero Charger
 * Hero Roller
 * Hero Blaster
 * Hero Brella
 * Herobrush
 * Hero Dualies
 * Hero Slosher
 * Hero Splatling