From their Website
Black Mesa is a 2020 first-person shooter game. It is a third-party remake of Half-Life (1998) made in the Source game engine.
BlackMessa servers require 2 ports to be open, the SourceTV port can also be opened for spectators.
| Port | default |
|---|---|
| Game/rcon | 27015 |
| SourceTV | 27020 |
| ClientPort | 27005 |