Crystal Quest

Cheats:

Extra lives and time:
Press [Tab] just before entering the portal at the end of a level. After your
ship disappears, leave and allow some time to pass. Return to the portal and
press [Tab] to receive extra lives and time.

Easy points:
Your score is limited only by your patience. This is because dumples bring
2,000 points apiece. On level 5, the game throws nothing but dumples at you.
And before level 11, and in particular on level 5, you will get a free life
every 15,000 points. If you can average seven and a half dumples killed per
life-losing mistake, you will break even. If you can do better than that you
can play level 5 indefinitely, gradually collecting more and more lives and
points.