[Blaaaaaaaah]

You get 1 reroll per 250 points, can store up to 500 (2 rerolls)

You get after every aram you complete: 30 points + (1 x # of champs owned)

If you have twenty champs you get 50 points per game, you get 1 reroll every 5 games.

I just got 70 champs, so that's 100 points per game, 2 rerolls every 5 games...

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