Pilot a fighter diagonally into a floating fortress drawn in isometric 3D. Your ship has an altitude: read its shadow and the altimeter to slip through wall windows, hop over low walls and pass force fields above or below. Turrets shoot up at you, radar dishes are worth 1000 and fuel drains all the time, so shoot the fuel tanks to keep flying. Between fortresses, open space brings fighter planes at every height — match their altitude to hit them. Free, no sign-up — play right in your browser.