The Crater is a massive crater located in the Splatlands that has an upside-down structure similar to the Eiffel Tower. It also contains the first four levels for the single-player campaign, Return of the Mammalians.
When the player finds themself in the Crater, they meet a retired Craig Cuttlefish. He believes that the sudden disappearance of the Great Zapfish is caused by the Octarians yet again. He recruits the player and calls them the new Agent 3. For the first four levels of the campaign, he will help them out like in Splatoon and the Octo Expansion. After a sudden fight with DJ Octavio, who seeks answers for the sudden disappearance of his troops, the ground falls and Smallfry, Cap'n Cuttlefish and Agent 3 fall into Alterna. Agent 3 and Cap'n Cuttlefish get seperated afterwards.
There are two Loot Anchors hidden on the map. The first, which is close to the first kettle contains a Zapfish doll which can be used in the Locker Room to decorate your locker, while the other is close to the third kettle and hides a pack of cards which can be used to play Tableturf Battle.
Craig Cuttlefish’s dialogue at the beginning of the mode is a reference to the very first game.
The player can return to the Crater at any time by simply interacting with the Zapfish doll at the Squid Sisters Camp on the first site, Future Utopia Island.
