0. Game is 40 rounds. Only 1 upgrade from each cat each round, so it takes time to level to max
Bonus perfect base, does not add to your points-to-spend score, as far as I've noticed.
Try to save up at least a bit of points so you have a buffer if you suddenly encounter a much harder level.
Overall rocket launcher is the way to go, I used the nuke-spell (top right corner) when I desperatly needed a reload with the rocket.
1. Get bow (or be rly good at the rock tossing)
2. Get hand gun, upgrade to machine gun
3. Level speed and power a bit
4. Level a bit of health and more importen, shield.
5. Upgrade to rocket launcher (gun lvl 5) *with piercing shot 2 you can hit ALOT of enemies
6. Level Special powers - piercing shot 1 is awesome, piercing shot 2 (level 3 special power) is even better)
7. Level ur base to max once you've got the above.
The only level I really had trouble with (lag fest) was the final one.
 "Cursed Treasure: Level Pack!"){kind=icon}
 "Age of Defense"){kind=icon}