Oasis is a strategy/puzzle game depicting the journey of an Egyptian prince to unite the fragmented kingdoms of his father's domain. Players explore the sorcerous fog that has descended on these kingdoms, uniting lost cities to fend off barbarian hordes.

Searching the kingdom uses a mechanic similar to Minesweeper, but with the difference that there are no harmful clicks. Each click removes fog from one space and reveals some information about what may be found in nearby spaces. Alternatively, once the player has removed enough fog to reveal useful terrain features, they may use a turn to instead build roads between cities, search them for hidden treasures, or take other actions to prepare for the barbarian hordes.

When the player runs out of turns, the barbarians arrive (from where?) and attack. The player will have ten seconds to move people to the nearest city (if the player built the right roads!) and then it's out of your hands. Victory depends on having made the right preparations. So while every click on the map is good, they may not all be equally good for your current situation.

The full version of the game includes the Pharaoh's Challenge, a selection of campaign games each telling a different story, and each using different variant rules on the basic game.