The diamond dealer is threatening to kill Ray, so he wants you to take him out. Off you go.
He's at the Majestic Hotel, so make your way over there now. Once you arrive, walk into the mission marker and watch the cutscene. You'll need to take the elevator upstairs.
Once you get up, you'll see a load of guys who tell you that you're not welcome. Take out the guy closest then run to the wall and take cover. Lean around the corner and fire at the enemies. Kill them all, then move down the hall way. Kill the remaining enemies at the end of this hall section, then make your way upstairs. Kill the two or three guys who will come through the door, then make your way through the door yourself.
Use auto-aim and lock on and kill as many of the enemies in here as you can. Once you've taken out a few, run in and take cover behind the couch. Finnish off the rest of the enemies at the back of the room, then move towards that area yourself. There'll be a few enemies in the kitchen, including one of the diamond dealers, so kill him and grab the health pack from the wall, then head upstairs and kill the dealer packing his suitcase in the bedroom. Might as well waste his wife too.
Standing On The Rooftop...
After that, head upstairs to the roof. There's a few guys up here, but you can lock onto them through the window, so you shouldn't have too much trouble taking them out.
Once they're dead, you'll get some police attention, and your objective is to escape the hotel. There are some guys on the rooftop slightly below you, so take cover and pick them off. Grab the ammo and body armour from the roof, then move down the stairs onto the lower rooftop. You'll find an elevator platform which you can control to get yourself back to ground level.
- Make sure you're fully stocked up on armour and AK-47 ammo for this mission.
- Take it slow and use cover when possible.
- After the mission you may need to lose a wanted level, so be prepared to escape.