When you start the level, stay in the shadows of the trees to avoid being spotted by the sniper. This may require a few attempts. When you see the tunnel, run towards it. Run along it towards the Agency pick-up. When get near the end of the tunnel, crouch and take out your Anesthetic. Look at your map and wait for guard patrolling there to walk away from you. Follow him. When he stops, use the Anesthetic on him. Make sure to use all five bottles. Then, take his clothes and pick up his gun. Save the game at this point. Note: In this level you do not have to complete your objective. Look at your map to see where the exit sign is located. Run when you can, but when you are near snipers walk. Try to stay far away from guards as they will check your I.D. and begin shooting at you. When you come near the exit again, stay as close to the mountains as possible and run. You will be able to complete the level with a Silent Assassin rank.