Splatoon Raiders, though presented primarily as a single-player experience, includes multiplayer functionality that enables players to team up with friends. The game does not explicitly guide players toward discovering this feature, which operates similarly to multiplayer modes in Splatoon 3, with the notable restriction that local wireless play is not supported. Local cooperative play, including split-screen, is also unavailable.
To initiate a multiplayer session, players must first complete the introductory missions. Following this, players will gain access to the team's ship base, where a radio can be found in a corner opposite the treasure bot. Interacting with this radio is the gateway to multiplayer.
Upon first use, the radio prompts players to select a nickname for online play. While the system defaults to the Nintendo Switch's user name, this can be changed, provided it complies with Nintendo's online terms of service. Players can then choose between online wireless and local wireless modes. It is important to note that the local wireless option does not facilitate local co-op; each player requires their own Nintendo Switch system and a copy of Splatoon Raiders.
The online wireless mode allows players to join existing rooms, invite friends from their console's friend list, or create their own private room with a password. Playing in a party with friends will cause the game's balance to adjust, leading to an increase in enemy presence and a generally more challenging experience during raids.