THEBONUSBUYSLOTS

Land-based machines once offered a distant ancestor of the idea. So-called buy-a-pay games required the player to insert extra coins to activate additional paylines or unlock a bonus symbol, meaning certain features were simply unavailable at the minimum bet. Modern purchase bonus round slots take the concept much further by selling direct entry to the feature itself rather than merely the eligibility to trigger it. The older mechanic still exists on some cabinets, though few players recognise the lineage.