Try the game of Doodle God. Start with four elements: air, earth, fire and water and combine them to make more.
For example, combining air and fire will create energy. Combining earth and water will create swamp. Put swamp and energy together to get life.
There are 114 elements to discover within 14 groups: an extremely addictive and occasionally frustrating game.
Additional
For anyone mad enough to play Doodle God through to the end, try Doodle God 2
