New slot machine titles seem to be in a race to see who can include the most number of bonus rounds in their game.
A game’s design, pace and overall session length are influenced by the addition of bonus rounds.
To design a game that incorporates multiple bonus rounds requires an understanding of the games’s math, psychology and business model. To learn more about bonus rounds and how they influenced contemporary slot game design, read on.
Bonus Rounds Offer Games a Second Layer of Design
Bonus rounds offer slot games a second layer of game design that is beyond the base game and its fixed paylines. These designers face a trade-off of adding an interesting bonus round versus adding more game features. Designers strive to make their casino online games stand out by finding interesting ways to give players an interactive feature such as free spins or bonus picks. Bonus rounds are essentially a side game that determines the outcome of the base game, and are influenced by the game’s random number generator (RNG). Every feature in the base game is influenced by RNG, which randomizes the outcome of each and every spin.
An interesting bonus round allows game designers to differentiate their titles from the hundreds of other slot games released every year. Players focus on themes, features, bonuses and how each game is designed to incorporate volatility. Game designers and marketing teams create short promo or preview videos to showcase interesting bonus rounds and features, giving players an easier way to evaluate what game may be fun to play.
Bonus Features Echo the Tension of Live Wagers
Like sports wagers, bonus features emphasize suspense stemming from an uncertain outcome. Such an outcome determines the result of the bonus Pakistan betting feature, and players of cricket find the same excitement when they assess wagering options. In both examples, a wager is made, and suspense derives from waiting on a result. A free spins feature extends that suspense by playing several spins at the stake of the feature. A multiplier increases a win by the same factor as boosted odds.
The “volatility” of a game informs the balance of how often a bonus feature is triggered versus the size of that win. Developers set such parameters in a game’s math model, which informs the long-term expected value and return to the player. A high-volatility game may reward its bonus feature roughly once in 200-300 spins on average. The published return to the player already includes the expected value of all bonus features.
Common Bonus Formats and How They Work
Different formats of bonus rounds interrupt the monotonous nature of base game spins. Knowledge of these formats can give insight into the purpose a designer aims to serve within a game. Below are the main formats used by designers.
- Free spins: These formats award the player extra spins that sometimes have special symbols or multipliers.
- Pick and win: This bonus awards a prize based on what the player selects from a set of options.
- Wheel bonus: A prize or multiplier is awarded from a spin of a wheel.
- Hold and spin: This bonus format uses special symbols to lock in a win, and reset the reels to award additional spins.
Though these formats vary, they are based on predetermined probabilities set by the game’s math. Often in a pick-and-win bonus the prize is decided beforehand, and the feature is simply entertainment.
Anticipation vs. Prize Value
Psychologists note that variable rewards often lead to better, longer-term engagement. Bonus rounds are designed to build up to a trigger. The sounds and animations of the features often amplify the sense of anticipation. Because of this, a number of game studios often point to the trigger as the emotional peak of the game.
Features allow games to pay out in larger, infrequent bursts as opposed to steadier, smaller, more consistent payouts. Since payouts are governed by the same underlying probability as the core game, these features help shape volatility in a way that is appealing to a broader audience. Bonus triggers are relatively infrequent compared with ordinary spins, which is why they feel special when they occur.
Where Math Meets Showmanship
Mathematically, various ways to hit bonus triggers allow game designers to set the volatility of a game to their liking. Knowing how the games work allows players to keep the expected return of a game in perspective. Understanding the mechanisms of a game keeps every spin in perspective.
