The Bonus Symbol in brief
Bonus Symbols are trigger icons rather than standard paying tiles. Landing a set number of them, often three or more, opens a secondary round: Free Spins, a pick screen, or a wheel. They tend to be themed to the game, styled as chests, coins, or badges instead of the usual card ranks. In my view they earn their place through what they unlock, not through direct line payouts.
Role on the reels and payouts
Unlike a Scatter that often pays a scatter win as well, a pure Bonus Symbol usually pays nothing on its own. Its whole value sits in the feature it triggers. The paytable of most releases lists the trigger requirement rather than a coin figure. I tend to check whether the symbol can appear on all reels or only a few, because restricted positions make the round much harder to reach.
Historically the mechanic was reworked more than once. Early builds simply needed three matching icons on a payline; later iterations bolted on the retrigger layer so extra symbols during the round extend the spins. Personally I rate the versions that let you retrigger, since a single trigger can otherwise feel thin against the base wager.
Who invented Bonus Symbols?
Crediting the idea to a single studio is awkward, since it was borrowed and refined from older land-based machines. It all began around the shift to feature-driven video slots, when a dedicated trigger icon replaced payline-only bonus rules. Over successive releases it evolved into the standard gate for Free Spins.
Slots where the symbol shines
Red Rake lean hard on themed Bonus Symbols across their catalogue, and titles such as Mystic Fortune Deluxe and Super 20 Stars use them to open extra rounds. Amatic Industries keep a more classic style in games like Hot Fruits 100, where the trigger sits among fruit and lucky-seven icons.
Elsewhere I would test Wild Wild Riches and Book of Ra Deluxe to see two different approaches: one modern and feature-heavy, one retro and stripped back. Average RTP across these lands near 96.7%, though the max win varies wildly by title, so read each paytable before committing real stakes.
FAQ
On how many slots do Bonus Symbols appear?
Does the Bonus Symbol have a special function?
Which Bonus Symbol slots have the best RTP?
Can you play Bonus Symbol slots for free?
How many Bonus Symbols are needed to trigger a round?
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