For example a double diamond symbol appeared on the third reel can give you a 50 x bet bonus.
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https://democratstoughlove.com/showthread.php?tid=25314
https://planeswalkers.org/viewtopic.php?t=104723
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https://www.ukalachat.net/forum/index.php?topic=2801.new#new
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https://boards.streamweaver.app/showthread.php?tid=15338
https://www.ukalachat.net/forum/index.php?topic=5144.new#new