Beta 2:
Excellent improvements all around! Able to get past wave 10 relatively easily without those cheap enforcer shots :D
The enforcer spawner balls ... is the collision detection based on the actual size of the pulse at the moment or is it based on the full size of the enemy?
What I mean is, when the spawner is BIG it takes up more of the screen than when it shrinks to the smallest point in the pulse. But even in that state, the collision detection appears to be calculated based on the BIGGEST frame of the sprite - which feels cheap because you can be killed without actually touching the spawner in its smallest form without appearing to touch it.
Otherwise? Looking really solid!