Attack Speed - 5
Multishot Chance - 10
Nova Chance - 10
Resource Bonus - 18
Resource Wave - 28
Health Regen - 2.5-3
Add to Damage, Missile Speed, Health Regen and Health the entire game. You generally don't want to spend more than two missiles on one of the small targets. I'm putting my special resources into Attack Range.
The Nova knocks the crowd away so that your Attack Speed and Multishot can take them down while your Health regenerates.
I've gotten to level 46.
Mind you, I've got tier 15 researched so I start with 1161 resources. Also, the Resources Bonuses are a must.
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