Good idea, although I would deviate from 1v1 tournament idea. Skills are so vastly different. You either have to implement divisons (bsg, pd, m), with all associated problems of smurfing, or change format. Say, play FFA, or "all random". I know there are lots of nice people, who would love to play in a charitable event, but some skilled players may just come for the money. Making $25-30 on a $5 investment for beating nooblets is not that bad of a deal, but would totally ruin the competitve (read - fun) part of the tourney.
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