To win at sphere break every time you play all you need is the four basic coins you get when you first start playing and an Iron Giant coin. Iron Giant coins can be won by playing the guy right behind the little guy you get your first coins from(he cannot be played until Chapter 2). Once you have the Iron Giant, practice against the little guy and multiply it. Then when you want to win just use an Iron Giant and three other coins whose numbers are 1, 2, and 3(Three of your four first coins are worth these values). Now, since the Iron Giant has Multiplier Echo on it, whatever the number of the core sphere is, make it x1.

Example: Core Sphere=7, your total=7
Core Sphere=4, your total=4

Since you have 6,1,2,and 3 as your main coins, you never even have to use a border coin! 1=1, 2=2, 3=3, 3+1=4, 3+2=5, 6=6, 5+2=7, 6+2=8, 6+3=9. You've got all the number covered!

Just keep sphere breaking x1 and by turn 13 you will be over 80 for your Quota!!!