Return of the Mammalians

Template:InfoboxMode Template:Todo Return of the Mammalians is a single player game mode in Splatoon 3. It involves the player donning a Hero Suit and venturing into the Crater and Alterna (the setting of the story) to defeat the Octarian army.

Story

An Inkling or Octoling, accompanied by their "little buddy", Smallfry the Smallfry, are scrap hunters who search for junk gems by day and splat it up in Turf Wars on the side. When they go through a manhole, they meet Craig Cuttlefish, who dubs them the new Agent 3 of the New Squidbeak Splatoon. The New Squidbeak Splatoon's mission is to stop the continued fight against the unruly Octarians.

In order to get through areas, you have to take care of the Fuzzy Ooze, which Smallfry can eat as long as you have the right amount of Power Eggs

After defeating Octavio, Cuttlefish and Agent 3 get separated, which leads to them meeting the New, New Squidbeak Splatoon comprised of the old Agent 3 {now Captain} and the Squid Sisters.

The New Agent 3 is also aided by a robotic assistant named O.R.C.A., who helps guide them through Alterna.

After getting to a certain point, Deep Cut makes their entrance and makes it clear that all the loot in Alterna belongs to them. Later, Agent 3 has to defeat each of them to continue.

Quotes

“	SRL historian here with a pro tip. Want to learn about the weird world of Alterna AND brush up your skills with all kinds of weapons and varied terrain? Check out Story Mode! Just follow the strange old man into the Splatsville sewer to get started. Wow, new sentence. Another Story Mode tip: most stages allow you to choose from multiple weapon loadouts. So you can sharpen your skills AND take advantage of a weapon's particular strengths to survive. That said, sometimes you'll have nothing to rely on but your wits... and maybe a Zipcaster.	”
— @SplatoonNA on Twitter^[1]^[2]

“	It's not all multiplayer mayhem in #Splatoon3, you know? Dozens of single-player stages filled with unique tricks, tests and... hairy Octarians await in Story Mode.	”
— @NintendoEurope on Twitter^[3]

Trivia

This is the only single-player campaign that does not have "Octo" as the first word.
New Agent 3 has two styles of the Hero Suit. A post on Nintendo's official website hints that they are "each suited to different situations".^[4]
Unlike Octo Valley and Octo Canyon, the player can use a non-hero weapon in this campaign.
Additionally, this story mode bears multiple similarities to the Octo Expansion. This includes being able to choose between different non-Hero weapons, a similar interface and heightened freedom as opposed to the previous two Story Modes' linear progression.
In a post from Splatoon's Japanese account, an Octoling can be seen in the Hero Suit, confirming that Octolings will be playable in the single-player campaign of the base game for the first time.