GTA IV with the icenhancer mod. I've seen screens from GTA V with mods as well and they're beautiful but I'm not sure if it can compete with the work they've done on GTA IV tbh. Someone who's tried both got to say something about this.
GTA IV:
Bioshock Infinite got BEAUTIFUL scenery and may be worth a try as well.
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I'm not a slave for entertainment, I'm entertainments personal slave,
So deep into writing I'm concerned bout the text on my grave.
www.youtube.com/watch?v=gV8ozGcGJ6o