Rising Storm 2: Vietnam
Link: Save 75% on Rising Storm 2: Vietnam on Steam
Red Orchestra Series’ take on Vietnam: 64-player MP matches; 20+ maps; US Army & Marines, PAVN/NVA, NLF/VC; Australians and ARVN forces; 50+ weapons; 4 flyable helicopters; mines, traps and tunnels; Brutal. Authentic. Gritty. Character customization. And napalm in the morning.
Configured for both Windows and Linux (using Wine and Xvfb on Linux).