Tom Clancy's EndWar

There are a few ways to accomplish this but the easiest is to use Artillery and a spotter. This is also possible against the A.I but easier with a boosting partner. You will need to deploy one artillery and one Gunship. Have your partner send a weak unit like a transport to a location on the map. Now, move your gunship closer to the enemy unit so that it is at the edge of the Gunship's vision (SitRep may help to show this). Once your Gunship is in position, switch back to your Artillery. The enemy transport should now be visible to the artillery. Direct the Artillery to attack. If done properly, your Artillery unit should not show up on your partner's radar. When the transport has been destroyed the trophy will pop.