The other 15 credits are to enable the Match Card feature. 15 credits are for three hands of five credits each, based on standard Triple Play video poker.
The cost is that the player must double his bet, and wins are based on half the total bet only. If the Match Cards match any cards in the player's hand after the draw, then he will win multipliers. The twist is after the draw, the game will choose three cards, known as the Match Cards, from a separate deck, not including any cards the player discarded. The game plays like triple-play video poker, but with a twist.
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