I think it's somewhere around the 15 hour-mark IIRC, though it really depends on how much of the optional stuff (side tombs, collectables, exploring, etc.) you do. The Pro version has three modes, a high framerate mode (which has an unlocked framerate at 1080p but I think it's mostly in the 45-50FPS ballpark from what I remember reading, not a locked 60), a 4K mode (which really helps with the game's aliasing issues) and an enriched visuals mode (which adds some of the previously PC-exclusive graphics features to the game at 1080p/30) so you get a good amount of control over how the Pro's additional horsepower should be used. As for the game itself... well, if you liked the first reboot game, you'll love this one. If you preferred the classic Tomb Raider games or if you can't stand bad writing and story-telling, you should steer clear of it
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