Herobrush

The Herobrush is a brush in Splatoon 2 that is exclusively used in Octo Canyon.

Description
The Herobrush has a very visually similar design to the Octobrush but wears the usual black and lime-green color scheme of the Hero Weapons. It is usable in Octo Canyon and can be upgraded one level. Like all hero weapons in Splatoon 2, they come with switchable sub weapons of Splat Bombs, Curling Bombs and Autobombs. It is loaned to Agent 4 by Sheldon during the level Underground Expressway, and can be used in other missions after beating the level. Beating all missions in Octo Canyon with it unlocks the Herobrush Replica for purchase at Ammo Knights.

Herobrush Replica
The Herobrush Replica is a reward in Splatoon 2 unlocked for purchase at Ammo Knights by beating all missions with the Herobrush. It is a brush-type main weapon and is visually identical to the Herobrush. Despite its unique appearance, it is simply a reskin of the Octobrush; sharing the same stats and loadout (Autobombs and the Inkjet).

Trivia

 * Unlike every other hero weapon (except the Hero Roller) where the design and replica are based on the main weapon in its class or sub-class, the Herobrush is based off the Octobrush and not the main weapon of the brushes, the Inkbrush. This is presumably due to the fact that the Octobrush is a more of an all-rounder and can provide a better singleplayer experence.
 * This may also be due to the fact that the Octobrush was released with the launch of while the Inkbrush was not.