Tips for 100% the game:
For story mode, you should do whatever you'd think fit your playstyle. Everything gives you 100% payback when you sell them, cash is never lost, so EXPRIMENT.
My personal combo: The Bullet+Russian Roulette+Ram Jet+Fins=Too much speed.
After you open any card pack you want(I'd have to recomend the rocket pack) Try grinding classic mode. If you get the dubstep drive... oh classic mode will be TRIVIAL. I completed classic with my bullet+dubstep in 23 days. That will be your pack grinding method.
For achivements, as stated above: Expriment! This game has tons, and i mean TONS of stuff for combinations, Here are my sugestions:
-For airtime: Use lightweight bodies+hover style stages(E.g bashee or helicopter)
-For speed: Bullet. Just use Bullet. No addition means needed. A bullet+high acceleration stage=Ez achivement.
-For payload: Attempt to find the superhero body in the penguin power pack. That will pretty much gurrantee your easy win in payload.
Tips to defeating the Thunder:
1.If you have alot of money (about 1500) buy the treasure chests it increses (sorry bad English) your money income.
2.After the first boss buy your weapon upgrades. If you don't' you won't make it.
3.When you at the third boss, sell your treasure chests and buy another weapon, ship speed, firing rate. Then wreck the Thunder!!!
This is my order of upgrades when I have $2600:
Begining: level 2 ship, +4 treasure chest, +3 treasure chest
After first boss: level 3 ship +4 weapon
After second boss: level 4 ship, (what +4 upgrade you want. I perfer +4 firing rate. If you have trouble pick up +4 ship speed)
Right before third boss: sell treasure chests, buy +3 weapon, +4 ship speed, +4 firing rate.
And then WIN!!!!!!!
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