Arma 3. Treated myself to the SOG Prairie Fire (Vietnam) mod, I had read the Steam reviews and the AI was a mixed bag for solo play, it put me off.
Well, this evening I took the plunge and after a few test missions in the Editor, left super impressed. The AI (for Arma) is really cool, its great to be back to using iron sights.
Having owned Arma 3 for years, I dabbled but put off with the super human AI and the 2035 campaign never really grabbed; always reverted back to Arma 2 or Op Flash for the Cold War vibe.
With the exception of Op Flash, I am not bothered about the single player campaigns in Arma as the game is all about the Editor and creating your own missions. I am a casual gamer so my Editor skills are limited, usually consists of setting up some firefights, only it is awesome when you set up flying jets that bomb or paratroopers drop out - the immersion is incredible. In SOG, the AI platoons (20 men) was a surprise, also a decent AI mortar crew which makes a change to see take out the enemy. The sound and environment is awesome. The soldiers are far more vocal so it adds to the immersion immensely.
Highly recommended if you fancy something different and happy to put some time in to create your own scenarios.