Wargame: Airland battle
It's in beta right now, but still great fun.
http://store.steampowered.com/app/222750/Ok, how to describe this. It's a modern era stratergy game. Imagine crossing company oh heroes with RTW style battles but ARMA realism.
There's an INSANE level of detail. You have to resupply your own men, #ap and #he, armour, movement speed, infantry transports.
The beta is multi-player, you build a "deck" of units, the more units within a group (ie, infantry, planes, vehicles, tanks, logistics etc) the more expensive it becomes. You have to try and build a well rounded deck. The game has true line of site, but if your recon can see something that your long range artillery can't, you can still bombard it. You have to use true style tactics to achieve victory, ie you NEED to support your aggressive groups and you need to protect your areas, planes can be long range.
I'm really bad at explaining this, but there's a stupid amount to cover. Steep learning curve, a million different ways to do stuff.
Graphics wise, it's great. Being a strat game, you spend a lot of time zoomed out, but you can zoom in close, I mean REALLY close and it just looks wonderful. Explosions, tracers, missiles, rockets, shells, smoke, everything is done amazingly.
http://www.youtube.com/watch?v=ECTcBWF6ig8 - Gameplay (no commentary afaik)
Battles are up to 10 vs 10. Many nations, US, UK, Canada, France, Germany, Russia, Swden, Denmark and more.
Also deck bonuses, IE you can choose to select from one nations armoury, which limits you but lets you deploy more troops, or you can specialise into mechansied which gives your vechiles more exp but less points to spend on recon or something.
Really fun game, especially when you play with friends