Stalker: Clear Sky → Hospital
We're required to get behind the sniper and shoot him. It's not really that difficult. Be careful, as triplets of enemies will occasionally appear on the other side of the hospital courtyard.
You'll have to complete the next stage without support. After jumping into the wall opening, immediately go through the left door to the stairs. There, kill a couple of Monoliths. A military helicopter appears, shooting everyone in sight. Several Monoliths will run up the stairs, fleeing from the helicopter. After they're dealt with, grab the machine gun, stand in the doorway, and destroy the helicopter. This should take at most thirty rounds.
The rest of the path will lead us to another courtyard, at the end of which another machine gunner is sitting behind a makeshift shield. Besides him, there will be a dozen Monolith soldiers armed with assault rifles in the courtyard. It's best to hide in the vestibule through which we entered the courtyard. To successfully complete this stage, you only need to hold out for exactly one minute.
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