The longer a battle goes on for the quicker you will up a level. Or if your like me, just do a shit load of battles. The only way to gain experience to up a level is by hitting the opponent, so naturally the more times you hit him the more experience you gain and the quicker you will up a level. The advantage is when you up you gain 50 health, and a bunch of points on all your rappers catagories like agility defence strength etc... This in turn makes your rapper stronger.

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