This one is definitely an old school FPS. It's quite tough, totally linear and based only on gunfight and simple environmental puzzles. No sidequests, no factions, no perks, almost no exploration. You literally walk through a tunnel for 12/14 hours, depending on your ability. Sometimes you can take different passages to find ammo, gas mask recharges or stimpack, but the main path is always one, even in the levels on the surface, a pity. I played and finished it, because it has a unique atmosphere and a great setting: the NPC’s are well written and the graphics are still excellent. Dialogues and voice acting are ok, for a FPS. But the general gameplay is too old for today. We have no replayability here. For this reason my advice is to buy it only on discount, because once you have finished it it's very unlikely to play it again
