Hey guys,
The best thing what the developers can do is a coop mode for this mod 
I love the mod and want to play it togheter with my friends
so Developers Please make a coop mod 
it would make the game perfect.
Synergy has added mods in the past. That’s likely the best bet.
Even if developers will make a co-op modification for this game, it won’t happen any time soon, since the game itself is not fully completed yet.
The devs have already stated that they’re not going to add co-op mode, it would require changing every map to accommodate multiple players, which is far too much work, especially now that the mod has been released. There’s also the balancing issues that come with having more than one player, and having to deal with players dieing properly.
Another question answered.