On the planet Tantris are the Triphylios of Nem plants, which help keep the populous alive and the vast forests pure. But the increasing amount of industry has resulted in high levels of pollution, damaging the plants and killing off the forests.

To deal with the forthcoming doom, the Gnostics constructed the Leg, a heat probe that has the capability of entering polluted areas, absorbing the heat of the Zeal smog flames, and giving that heat to the three plants. It can hop up plants and walls, and slide along the floor for faster movement. To defend itself from dangers – which include wildlife and acid rain - the Leg can shoot the Ball which it carries, or use a smart bomb if the going gets tough. Contact with any danger loses the Leg energy. Chalk can be collected which protects it from the acid rain.

The Ball can also be thrown out to collect heat, which must be stored in the Leg so that it can be given to the three Triphylios plants. If it has stored enough energy, the plants open petals to block the acid rain.