Grenade Hangman Trophy in Uncharted 3: Drake's Deception

There's a small chance this will come naturally depending on your style of play but more often than not, this one will need to be farmed as hanging from objects and throwing grenades just simply doesn't occur as being the most efficient way to waste some enemies. Throwing a grenade while hanging works pretty much the same way as in ordinary cover, as per the tutorial in Chapter 7. Of course, you need a supply of grenades also, unless you happen to score a throwback but these are even more rare than normal hanging grenade kills. There's a couple of different ways to farm this as detailed below:

Chapter 11 - Abducted

Yet again, the same area where many other trophies are farmed is a decent place to farm these kills. Once you get to the area with all the bad guys on the barges and in the boats, swim to the nearest barge and climb the few rungs to pick up the grenade in front of you. Without climbing up any more, use to aim your arc and throw the grenade at the guy on the other side of the barge just beyond the crates. Once he dies, restart checkpoint and repeat until you have all the kills required.

Chapter 16 - One Shot at This

As you ascend the hangar area on this chapter you will have a chance to stealth kill a patrolling guard through a skylight. Do so and he will drop a grenade, now jump up on the wooden container by the support beam and wait for a jeep to pull up, toss your grenade at it to blow away up to 4 guys at once, which is also great for unlocking Dyno-Might Master, check that description out for a video. Restart the checkpoint as required.