skill crystals

A skill with prize or skill with prizes (SWP) machine is a gaming machine which provides a payout (the prize) and whose outcome depends in part on the player's skill (the skill). They are contrasted with amusement with prize machines which, while interactive, do not depend on the player's skill in determining outcome.
SWP machines are a hybrid of games of skill and games of chance; the degree to which skill versus chance determines the outcome varies between machines, and may be set by operator parameters.

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