Hero Mode

Hero Mode is a single-player game mode in Splatoon. It involves the player donning the Hero Suit and venturing into Octo Valley to rescue Inkopolis' stolen Zapfish and defeat the Octarians.

Story
After the Zapfish, Inkopolis' primary power supply, are stolen, it is up to one Inkling, under the guidance of Cap'n Cuttlefish, to travel to Octo Valley and defeat the Octarian army.

World 1

 * Stage 01: Octotrooper Hideout ~ Catch That Zapfish! ~
 * Stage 02: Lair of the Octoballs ~ Splat Your Wat to the Top! ~
 * Stage 03: Rise of the Octocopters ~ Leap to Victory! ~
 * Boss 1: Squish, Squash, Smash... The Mighty Octostomp!

World 2

 * Stage 04: Gusher Gauntlet ~ Take to the Skies! ~
 * Stage 05: Floating Sponge Garden ~ Soak It Up! ~
 * Stage 06: Propeller-Lift Playground ~ Whispers on the Wind ~
 * Stage 07: Spreader Splatfest ~ Ink Stains & Teardrops ~
 * Stage 08: Octoling Invasion ~ Kelp Dome Showdown ~
 * Stage 09: Unidentified Flying Object ~ Trouble over Inkopolis! ~
 * Boss 2: Shootin' the Sneeze... The Dreaded Octonozzle!

World 3

 * Stage 10: Inkrail Skyscape ~ Walking a Fine Line ~
 * Stage 11: Inkvisible Avenues ~ Find Your Path ~
 * Stage 12: Flooder Junkyard ~ Renegade Robots ~
 * Stage 13: Shifting Splatforms ~ Midnight Rendexvous ~
 * Stage 14: Octoling Assault ~ Skrimish at the Skatepark ~
 * Stage 15: Undeniable Flying Object ~ Bluefin Sighting ~
 * Boss 3: Roll with the Punches... The Rampaging Octowhirl!

World 4

 * Stage 16: Propeller-Lift Fortress ~ Spin to Win! ~
 * Stage 17: Octosniper Ramparts ~ Inkredible Aim! ~
 * Stage 18: Spinning Spreaders ~ Time Waits for No Squid ~
 * Stage 19: Tumbling Splatforms ~ The Tentacles of Fate ~
 * Stage 20: Octoling Uprising ~ Battle at Bluefin Depot ~
 * Stage 21: Unwelcome Flying Object ~ Underpass Infiltration ~
 * Boss 4: Inkling is on the Menu... The Ravenous Octomaw!

World 5

 * Stage 22: Splat-Switch Revolution ~ A Change of Scenery ~
 * Stage 23: Spongy Observatory ~ More Ink, Less Stink! ~
 * Stage 24: Pinwheel Power Plant ~ Slip through De-fences! ~
 * Stage 25: Far-Flung Flooders ~ Inkling vs. Machine ~
 * Stage 26: Octoling Onslaught ~Rumble at the Rig ~
 * Stage 27: Unavoidable Flying Object ~ Skatepark Encounter! ~
 * Boss 5: Let's Finish This! Enter the Octobot King!

Gameplay
Hero Mode incorporates various puzzle mechanics and 3D-platforming elements. Gameplay has been compared to Turf War and Super Mario Galaxy, in the sense that it sees players splattering Ink to defeat enemies, transforming into squids, and traversing floating platforms. Your only available weapon in Hero Mode is the Splattershot. There are multiple different tools or Mechanics that make an appearance in the Singleplayer campaign.

Trivia

 * The player's Inkling wears a vest, headset, and futuristic shoes during Hero Mode. They cannot be purchased, but replicas are unlocked after completing Hero Mode.
 * Before or after any boss battle, creepy moaning and clanging can be heard in the background. This is assumed to be proof that the Octarian civilization is falling apart