Tom Clancy's EndWar

On the left pane of the mission results screen you'll see the status of all units that were deployed during that mission. It will say something like "10 units survived, 2 units killed, 1 unit promoted". For this trophy, you need to have a single unit of any type play in and survive 10 missions. They do not have to be consecutive missions. A unit can be downed (and thus Evacuated) but it cannot be fully killed. If you're boosting you will get this naturally while going for wins or games played, as you won't be engaging in any combat. If you're playing legit, the best advice is to only play Conquest missions and to keep a strong unit back near the deployment area. Legit players frequently unit-kill so playing a mode like Conquest where total Annihilation is not the objective will help.