i agree with doombringer759. you should use the exp you get from winning races as currency.
for example, i win a race and get 30 xp. my total amount is now 30 exp. i use that expierience to buy things, but i also use it to level up. it should say something like this:
Xp. Left: 0
Total Xp.:30
4/5. it gets too hard and it doesnt give u enough red pixels for red to lvl up. if u mess up once, u lose it. you dont even get another chance. other than that, good game.
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