GemCraft is a tower defense game where the player builds towers, arms them with 'gems', and sees off armies of invading monsters. A complex gem combining system allows the player to trade off various combinations of special abilities with raw damage from their gems.

GemCraft is a tower defense game where the player builds towers, arms them with 'gems', and sees off armies of invading monsters. A complex gem combining system allows the player to trade off various combinations of special abilities with raw damage from their gems.