Mystic Shuffle High-Lo

I was wondering of the Wizard or anyone else has played Mystic Shuffle Hi-Lo on Bodog? You have to guess whether the next card is higher, lower or the same. Same card is then used for the next in the series up to a maximum of twenty times. The twist- Each successive guess gives you a cumulative bonus for the next round from 1% to 5% added each time. The payout is typical for hi-lo, based on the card shown and what bet you make.I'm usually pretty good at statistics but I have no idea how to calculate the house edge with the bonus feature. Any ideas?