Visceral Games has confirmed the rumour that originated last year, but was named only because it was the fourth project and not because it included four-player multiplayer.
"That was an internal thing we had," senior producer James Nance said.
"We had [two Army of Two games] and then there was an expansion pack for Army of Two, so it became Four internally. It's not the fourth instalment, it was an in-development, working title. Now it's The Devil's Cartel."
When asked whether four-player multiplayer was considered, Nance responded: "We certainly talked about it, but we really focused on two-player co-op, that's our thing.
"We could have done competitive multiplayer, we could have done four-player or something like that, but we didn't think it was true to what the franchise is. Couch co-op, online co-op, we wanted to stick with that."