Stalker: Shadow of Chernobyl → Radar
You'll have to fight your way north along the road. Ignore the first right turn—it's a dead end (I wonder what they originally planned to do there?). The second turn is to Pripyat, but they won't let you through even with brain protection.
Besides the Monolith soldiers, your enemies here will be phantoms emerging from underground. Shoot them as they approach—they die easily, which can't be said for the Monolith stalkers. Be careful when approaching the wall—there are snipers perched on towers behind it. You can pick them off in a duel or ignore them by running into a dead zone.
Ahead is a broken section of the wall. If you wait long enough, Monolith soldiers will jump out of the hole to meet you. The entrance to the X-10 Laboratory is hidden. Climb the ramp into the train car sticking out of the tunnel and clear the last meters to the laboratory. The Phantoms won't leave you until you enter the X-10 Laboratory.
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