Hero Charger

The Hero Charger is a charger in Splatoon and Splatoon 2 that is exclusively used in single player modes.

Splatoon
The Hero Charger has a futuristic design with a black and lime green color scheme shared with all the Hero Weapons, and many blue lights that leave a small trail as Agent 3 moves. It behaves similarly to the Splat Charger, with great range, accuracy and damage. It cannot be upgraded with Power Eggs like the Hero Shot can be, and unlike the Hero Shot, it only comes with Splat Bombs. It is exclusively used by the player during the Inkling Girl amiibo challenges, and completing them all unlocks the Hero Charger Replica for purchase at Ammo Knights.

Splatoon 2
The Hero Charger has a new, sleeker design. It is now usable in Octo Canyon without the use of Amiibo and can be upgraded one level. It now comes equipped with switchable sub weapons of Splat Bombs, Curling Bombs and Autobombs, like every other Hero weapon. It is loaned by Sheldon during the level Octozeppelin Invasion, and can be used in all other missions after beating the level. Completing all the missions in Octo Canyon with the Hero Charger unlocks the Hero Charger Replica for purchase at Ammo Knights.
 * At Level 1, the weapon has blue lights, like in Splatoon. It functions identically to the Splat Charger.
 * At Level 2, the weapon has red lights. It has reduced ink consumption and vastly reduced charge time. The upgrade can be purchased at the Ammo Knights Enhancifier with 1,500 Power Eggs and three Sardinium.

Hero Charger Replica
The Hero Charger Replica is a reward in Splatoon and Splatoon 2 unlocked through various means. It is a charger-type main weapon and is visually identical to the Hero Charger. Despite its unique appearance, it is simply a reskin of the Splat Charger from that game, sharing the same stats and loadout, sub weapon and special weapon.

Trivia

 * Marie's main weapon is shown to be the Hero Charger or its Replica, likely from her time in the role of Agent 2. This is shown in her artwork for the Go all out! vs. Focus on healing Splatfest. In the final battle of Splatoon 2's Octo Canyon mode, she uses the Splatoon version of the Hero Charger to take out Callie's hypnoshades.
 * The weapon as seen in the first game and as used by Callie takes design cues from early AR-15 designs, most notably with the iron sights and carrying handle, as well as the shape of the handguard resembling that of early Colt models.