I am new here. Hello there, people!!!
Will the BM have cooperative play mode, such like Sven Coop?
(sorry for the really bad english). 
Weāre looking into a form of Co-Op MP. We canāt say what form (MP/SP) itāll take at the moment, but we are looking into it as a possible future feature.
Great news. You devs are doing a nice job.
Ai sven co-op was big a single player co-op or something would be great!
I am just waiting for some one to port and modify some of hl2 
Mās co-op maps cause some of them would be really fun with standard half life enemies.
Honestly, I would like to see a Crowbarās Collective version of Half Life: Decay, but I donāt know how happy you would be working on something like that, 
Best we have right now is: https://decay.half-lifecreations.com/
Its basically a port of the PS2 version, since Decay never got released on PC.
Just feel like chiming in (because why not) about co-op - out of boredom Iāve tried loading a few SP maps with maxplayers set to 2 (i.e, so it loads in DM mode), and surprisingly things seem to work pretty well. The biggest issues Iāve seen in trying it are areaportals (the one at the start of Surface Tension gets closed when the āroundā starts), level-changes (nonfunctional), and that the game seems to crash around certain NPCs (not sure which exactly, but it seems to be fine around Marines, Vorts, and headcrabs, at least).
I think, at the very least, itād be possible to make level-changes actually work through SourceMod or some such, so itās probably only a matter of time until someone devises a way to play co-op SP if itās not officially supported.
Give me a name of a map and Iāll do it. Im already remaking a sven coop map so pumping out a quick port should be easy.
damn I need to remember the map name, one of the hl2 M maps was a simple arena fight, 3 arenaās with progressively harder enemies must beat all 3 to beat the map. between them was better and better weaponsā¦ canāt remember the map name.