The past 25 years have seen slot machine bonus events evolve from wheel spins and funny cartoons into four distinct styles of bonus
By Frank Legato
Happy Silver Anniversary to the slot bonus.
Bonus events in slot machines eﬀectively began with the 1996 release of IGT’s Wheel of Fortune. The roulettestyle wheel spinning to canned audience cheers of “Wheel… of… Fortune!” began an evolution that has made the bonus event an absolute requirement of slot machine play.
The evolution has had many stops along the way. For instance, in the early 2000s, the main style of bonus events on video slot machines was the so-called “second-screen bonus.” WMS Gaming’s Reel’Em In showed a funny cartoon of ﬁshermen (and ﬁsher-women) in a boat, making comments in spot-on Chicago accents (WMS was based in Chicago back then), and the player would win bonus credits according to how big the ﬁsh were that were reeled in. It’s the granddaddy of modern games like Aruze’s Paradise Fishing.
Other funny cartoon bonuses could be had in games like IGT’s Lucky Larry’s Lobstermania and Bally’s Betty Boop series. One tried and true feature was the picking bonus—a second screen would display a ﬁeld of icons—rocks, beach balls or whatever—and the player would select to reveal credit awards behind them.
While there is still a variety of bonuses that have survived from the old days—ladder-style bonuses where reel triggers send the player up a ladder of increasing bonus styles, “mystery” bonuses that just randomly award a credit bonus without the player having to do anything, multipliers which multiply pays on winning combinations (that one began with IGT’s Double Diamond)—the slot machine bonus has evolved into four basic styles that are dominant in today’s world of slot machines.
The ﬁrst two, I’ve already mentioned, and they are deﬁnite crowd pleasers. First is that spinning bonus wheel that originated with Wheel of Fortune. IGT actually patented that bonus mechanism. In the early 2000s, if any slot-maker wanted to include a wheel bonus, a royalty payment went to IGT.
While patents normally remain valid for at least 17 years, IGT’s lock on the bonus wheel lasted 12 years, until 2008. That’s when a judge ruled in a patent lawsuit that a Bally slot with a wheel did not infringe on the IGT patent, opening the door for other slot-makers to include their own wheels.
And boy, did they ever. These days, one would be hard pressed to ﬁnd a slot manufacturer that does not have at least one game featuring a bonus wheel.
As for IGT’s Wheel of Fortune, it’s hard to count the versions of that game that the slot-maker has brought forth, right up to its newest games, which include a giant version of Wheel of Fortune, among many others.
IGT and others have made a lot of money oﬀ a basic premise: Players love to spin that wheel.
Another survivor from the old days is the picking bonus, which these days is more likely to be found in multiple progressive slot machines. The player will be shown a ﬁeld of icons, and prompted to pick to reveal symbols that each correspond to one of four or ﬁve jackpot levels. The player continues to pick until matching three of the symbols to win the corresponding jackpot.
The other two stalwarts of the modern bonus feature appeared much more recently. The ﬁrst, which has developed over the past decade to where it is ubiquitous on the modern slot ﬂoor, is the free-game bonus. In its most basic form, the player lands bonus symbols on the reels to trigger ﬁve, 10, 20 or more free spins. If those same bonus symbols land during a free spin, the feature is retriggered for another ﬁve, 10, 20 or more free spins.
The newest slots oﬀer a few twists on this formula. Some present a scenario in which you can win free spins numbering in the hundreds. (Aruze oﬀers an option to trade all those spins in for a single bonus award to save time.) Others oﬀer any of a number of ways for the player to choose the volatility of the free-spin round. For instance, the player will choose between a few free spins with lots of wild symbols and multipliers, or a lot of free spins with fewer extra symbols.
But the one bonus that is deﬁnitely trending these days is the so-called “hold-and-spin” bonus (also known as “hold-and-respin”). The player will be granted a ﬁxed number of spins—say, three. Special symbols that pay extra will land and stay in place, while the free-spin number goes back to the original three spins. This goes on until three spins with no special symbols appearing, triggering a bonus equal to the accumulated symbols, or until the entire screen is ﬁlled with those symbols, normally triggering a progressive jackpot.
It is known in the trade as a “persistent” style of bonus, and it also includes games that give the player a goal to achieve for a bigger award—thereby keeping them playing and glued to the screen.
This last style of bonus is still growing, and players are ﬂocking to a variety of hold-and-spin games. Of course, they are also ﬂocking to free-spin bonanzas, progressive picking events, and those ever-popular wheel spins. Happy anniversary to the bonus event.
We can’t wait to see what the next 25 years have in store.