Grand Theft Auto IV Walkthrough

The next few floors of this disheveled factory are easy enough to climb. There are two floors that you have to climb up (via debris, just like before), and there are plenty of enemies standing in between you and your ultimate destination. The enemies here are armed with a variety of weapons, from pistols to automatic rifles, so take cover as best you can (there's plenty of it around) and make sure to collect their guns when dropped. You're absolutely going to need their assault rifles for a little later (you'll see why), so make those a priority to grab.

After climbing the second debris pile, you'll see your target with a red arrow over his head (he's also represented as a red dot on the HUD). He'll bust out a nearby window, leaving his henchmen to deal with you. There's no rush here, so take it easy and methodically take out all of the enemies you encounter, remembering to grab their gear as you proceed. Then, you'll be able to emerge from the window, where you will be fighting on the roof. Don't bother pointing your gun at the main target, as you won't be able to hurt him or stop him from getting to his location. Instead, work your way towards his location each time you see him, killing enemies in between you and him. There are a few ladders to climb as well, so if you're at a loss as to how to proceed, simply seek out a ladder to climb to higher and higher areas.

If you follow the basic aforementioned techniques, you'll have no trouble eventually catching up with your mark, who will make an attempted overly-grand getaway on a helicopter. You'll have to take down the helicopter, which seems like a daunting task if you don't have an RPG in your inventory (and chances are, you don't), but this is exactly why we told you to be mindful of grabbing assault rifles dropped by dead enemies. With this powerful weapon, you can pummel the enemy helicopter, which takes off extremely slowly (you can shoot the gunner in the helicopter, but not your mark). Concentrate your fire on the rear rotor of the chopper. A clip or two of concentrated fire on it will set it ablaze, and the helicopter will crash back into the factory, taking your mark with it. This will end the mission in success, but don't be too hasty about leaving this area. You're high up, so climb down slowly!