Protect the crystals by blasting aliens with your shield. Blast the alien boss at the top 20 times to win. When you successfully land a hit on the alien boss, your ship will teleport back to the starting position. If you crash into an alien, including the alien boss, your ship will explode. When an alien reaches a crystal, both the crystal and the alien will vanish, and a new type of alien will be spawned from the alien boss. A or left arrow to steer left, D or right arrow to steer right, and W, S, up arrow, or down arrow to activate your shield.
Art and code by @gameray.
