At 10,000 points, your shot changes to either the wide or the fast shot. Every 10,000 points from then on, there's a chance that your shot changes to the other type.

Losing a life resets your multiplier. It is preferable to use a bomb rather than losing a life.

You get an extra life every 75,000 points and an extra bomb every 100,000 points.

Every enemy makes a different sound when spawning. If you learn these sounds and listen for them, you can know what enemies have spawned.