Defend the Earth! Maneuver the orbital mega-shield around the planet and attempt to repel the unrelenting horde of incoming asteroids.
You are humanity's only hope. You cannot fail. You must not fail.
It's all about the agile thumbs: tap on the right side of the screen to move the shield clockwise, tap on the left side to move counter-clockwise.
Tap and hold for continuous shield thrust.
Maneuver the shield around the earth to deflect incoming asteroids. Rack up points and climb the ranks from humble Cadet to awe inspiring Shieldlord.
But be warned: though the earth is resilient and can withstand four asteroid impacts, allow a third strike and it's game over.