Eco Phantoms

After six years away from Earth, your delivery contract is finally over, you've been paid a fat cheque and you can't wait to get home. As your ship gets closer and closer to the old beloved blue planet, the anticipation mounts.
But wait! What's this? The earth is an unfamiliar, grey husk! A vast alien mothership hangs above it, mercilessly sucking out all of its natural resources. While you were away, the Eco Phantoms arrived, and did this!

Now, you've managed to steal an Eco zeppelin craft and have gone down to Earth, to try to reverse the planet-draining process before it's too late. The Eco Phantoms have built several domes on the planet's surface, which house their buildings and equipment. You'll have to navigate through three of these domes, learning how to operate and maintain your alien craft, gathering resources, collecting data spheres, rescuing prisoners and engaging in confrontations with the Eco forces. Eventually, if you survive long enough, you'll be able to enter the alien mothership, where you will have to reprogram the main computer, to reverse the process and restore Earth to life.

Eco Phantoms is quite an ambitious mix of exploration, combat and strategy.