Clicking and holding fires the laser, which can cut straight through rock and baddies. Cut away two lines through a rock wall, and you'll then be able to push against it and create a pathway. Walls can also be cut to fall on top of baddies, or fling into them if you position the cuts cleverly enough. There's also a fair amount of shmup action on show, with aliens flying at you in formation.

http://www.nitrome.com/games/canary/