The Desert Oasis is a landform located on Xil.
The oasis is littered with remains that give insight into its past, the three still functioning xel'naga towers not withstanding. Formations akin to anenomes, coral, trilobites and sea shells can be found across its bed, similar to those found on Earth but much larger. This suggests that the oasis was once a marine ecosystem. However, the skeletons of giant creatures, some of which akin to Earth's mammoths, stand in testament to its variability over time, the fossil record shifting accordingly.
A series of trenches run through the oasis, demonstrating some form of electric discharge. Also in these canyons are the broken remains of terran aerospace craft and structures.
The oasis serves as a 2-player map in StarCraft II. A novice version of the map exists.
A large map, this makes early attacks somewhat difficult, not to mention that xel'naga towers allow early spotting along both ground routes and shorter air paths. Islands are provided for the safe gathering of resources.
Blizzard Entertainment. StarCraft II. (Activision Blizzard) Map: Desert Oasis (in English). 2010.