Oasis is much farther along in the terraforming process than Parker, so the terrain is covered in a large of grass and there are small plants sprouting up everywhere. The sky is bluer, the clouds whiter, and everything is a little more Earth-like. Due to this, Oasis has a much greater residential population and more wealth. Buildings are larger and their architecture reflects many different cultural styles brought to Mars from Earth such as African and Middle Eastern influences. The cars and trucks are also more advanced and clean. By the Oasis chemical plant there is a Light Walker near by. But be warned this Light Walker doesn't respawn.
Oasis is one of the six regions contained within the martian area of Tharsis.