This is a 1-Player mode, with the ability to have other human players on the controlling player's teams. However, the earning from this mode will only be saved to the progress of the first user. Progression through the mode is through the first player, as well.
The game offers a single-player experience where additional human players can join the controlling player's team.  However, the rewards earned in this mode are only saved for the initial player's progress. The game's progression is solely based on the first player's actions.