Despite all of the pre-release marketing for Gotham Knights showing off the four different heroes you could potentially play as, the game shipped with only two-player co-op. Whether this was an intentional design decision or some technical limitation remains to be seen.
Now, a free update for Gotham Knights owners was released by WB Games and DC that adds in the ability to play with the full roster. You and up to three friends can engage in some cooperative gameplay, but there is a catch. The catch here is that the four-player co-op is limited to only the new Heroic Assault mode.
Heroic Assault allows for teams of up to four players to venture into Gotham City's evil filled underbelly to "face off against enemies and complete challenges across 30 action-packed floors." Some of the foes encountered include the "highly advanced alien lifeform" know as Starro, the Conqueror. Yes, I looked it up and Starro is very much a real supervillain in DC Comics. It's literally just a big starfish.
Heroric Assault becomes accessible to players after reaching Case File 05 in the main campaign.
Another notable foe you will run into is the half-human and half-man blend that is Man-Bat. If you played Batman: Arkham Knight then you are perhaps familiar with him.
If you want a different co-op experience, the Showdown mode was also added to the game today. This one is a two-player co-op mode that pits players against souped-up villains such as Mr. Freeze, Harley Quinn, Clayface, and Talia al Ghul. Beating these bosses in this mode will get players new legendary gear blueprints along with new suit and Batcycle colorways.
Showdown becomes available to players after defeating each boss in the main villain Case File.
