Defenders of Oasis was created on 1992-09-18.
Crystal Defenders happened in 2008.
Dungeon Defenders happened in 360.
The Legend of Oasis happened in 1996.
Beyond Oasis happened in 1994.
Robotech Defenders happened in 1985-01.
Defenders of Dynatron City happened in 1992.
Oasis - video game - happened in 2005.
For most people an oasis is not particularly important, because most people do not travel through large deserts. But if you do happen to be travelling through a large desert such as the Sahara, you might well run out of water and need to get more at an oasis.
I drank from the oasis The oasis is in the desert There is an oasis in the desert.
A permanent source of water, such as a spring, makes an oasis an oasis.
an oasis is "une oasis" 'fem.) in French.