The Tower is a mysterious, gigantic superstructure of unknown origin. It is presumed to predate human civilization, based on cave drawing which depict it.[1]
Location
The Tower's precise location is currently unknown. Each character claims to be in its close vicinity[2]. It's uncertain whether they all see the same structure, or if there are multiple towers. Mars' explanation suggests it's in South America,[3] Sari lives near a structure which resembles 3 smaller towers,[4] Claw is shown to live in the Tower's shadow[5] and Ryann claims he lives in it.[2]