To solve 29 (on par): remove far right and most bottom blue balls. Remove the most left blue ball on the top stack and the topmost ball on the left stack. remove middle small little "pegs" that are directly under the red balls (one per stack). Remove horizontal rectangular peg and as soon as the big blue bar clears the other, vertical peg, remove that one as well. Timing is crucial.
A good strategy is first upgrade your cannon once and then get triple shot. Then upgrade your allies twice and your cannons twice more and your shields once or twice. Then, go for the yellow guys. Keep upgrading your shield and weapons and eventually, you'll need to start with the engine (because the yellow guys go fast). A guided missle upgrade should get you all the rest of the way. Note: you will need to destroy all the yellow before going after the red. If your mother ship starts getting attacked heavily, upgrade your allies
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