Tetro is a terrestrial planet located in the Harani Nebula, a helium- and hydrogen- filled dark nebula near the center of the Tevral Galaxy. It is roughly 170,000 light-years from the galactic core. It exists within the same causally-interconnected universe as Earth, but it is 22.5 billion light-years away, placing it 8.8 billion light-years outside Earth's visible universe. 82% of Tetro's surface is covered in water, and it has an atmosphere composed of nitrogen, hydrogen, and oxygen that is contiguous with the surrounding gases of the Harani Nebula. At 2,193,024 miles in diameter, it is 21,182,048 times larger than Earth by volume and has 76,695.6 times as much surface area. It is the only planet apart from Earth known to support life. Tetro is home to 16 intelligent species with a total