Operation Harsh Doorstop is a single and multiplayer tactical shooter with vehicles and large map support, it has mod support (a core objective of the dev) and crucially support for autodownloading server mods when players join the server.

https://store.steampowered.com/app/736590/Operation_Harsh_Doorstop/

The bipod system is quite impressive and overall OHD has really solid tactical shooter mechanics… but this isn’t only a game for realistic tactical shooter fans. Case in point some servers use the Casualfield mod which tweaks the game to play more like Call Of Duty.

https://steamcommunity.com/sharedfiles/filedetails/?id=3140994891

I am a huge fan of this game because the developer genuinely seems to be passionate about bringing a super solid big map multiplayer vehicle shooter foundation to the modding community, this game might seem a bit barebones right now but when you step back and consider how OHD is going to empower indie developers to easily get their hands dirty and start innovating on the shooter genre (and other kinds of games too) you can begin to see how exciting the future is for this game.