Submitted by: David K.
Watch out for the bosses – they don’t just come out at the end
of the level! Defeat them to get much-needed shield powerups
and tons of loot.
Upgrade, Upgrade, Upgrade:
The key to victory in the long term is keeping up with your
upgrades. Make sure your weapon power and fire rate increase
steadily as you play, since the best defense is a good offense.