[BlackFart]

Thank you for your advice, this is a great idea

So, following your instructions, this is what I've done :
I created a file serverfiles/csgo/gamemodes_ffa.txt with your gamemodes_server.txt, I just changed the exec part.
Then, I created 2 files called serverfiles/csgo/cfg/gamemodes_ffa(_server).cfg with the default deathmatch gamemode, and "mp_teammates_are_enemies 1".
Finally, in lgsm/config-lgsm/csgoserver/csgoserver.cfg I added (as in the _default.cfg) I copied/pasted the fn_params() {} and add `-gamemodes_serverfile \"gamemodes_ffa_server.txt\"` and changed gametype/gamemodes to 3/0

Now, I restart my server.
When I do ./csgoserver details (lgsm command), I can see in the command-line paramters the `-gamemodes_serverfile "gamemodes_ffa_server.txt"`

When I'm using grep on the logs to find this file or "gamemodes_serverfile" I get no match at all
In game, it's just a casual server (I imagine with the default settings of a gametype/mode 3/0

Could you tell me what I'm doing wrong ? :/
Thank you for your time