What a Bonus Feature Changes in a Slot Game
What a bonus feature is
A bonus feature is a mode that changes a slot's normal rules for a while. It is usually triggered by particular symbols, such as scatters, and it ends after a set number of spins or when a condition is met. Inside the feature, the game applies extra rules that the base game does not have. Understanding a game largely means understanding its feature, because that is where its design differs most from other games.
This guide describes the main types of feature, explains what each changes, and shows how to read a feature's rules before playing. It belongs to our game mechanics section.
The main types of feature
Free spins. The most common feature. A number of spins are played without deducting a stake, often with extra rules such as added wilds or multipliers. The rules state how many spins are awarded and whether more can be won.
Multipliers. A multiplier scales a win by a set amount. Some features apply a fixed multiplier, others increase it as the feature progresses.
Collection features. Certain symbols carry values, and another symbol collects them. Many fishing-themed games use this idea; our Big Bass Bonanza bonus-round explainer walks through one example using the studio's own description.
Hold-and-respin rounds. Special symbols lock in place while the remaining positions respin, usually for a limited number of attempts that reset when a new special symbol lands.
Cascades inside the feature. Some games apply cascading reels during the feature, so wins can chain within a spin. Our guide to cascading reels and standard reels explains that mechanic in detail.
What a feature actually changes
A feature changes three things about a game:
- Where the action is concentrated. In feature-heavy games, a large share of the excitement sits inside the feature, while the base game is quieter.
- How long you wait. A feature may take many spins to arrive, and it is not owed after a long run without one; each spin is independent.
- How outcomes are grouped. A feature can bundle several wins into one round, which makes results feel larger and less frequent.
What a feature does not change is the nature of the game as one of chance. Understanding a feature makes a game easier to follow; it does not make any spin more likely to win.
Reading a feature's rules first
The rules screen usually answers five questions. Write the answers down before playing:
| Question | Why it matters |
|---|---|
| What triggers the feature? | Tells you which symbols to watch for |
| How many spins or attempts does it give? | Sets how long the feature lasts |
| What extra rules apply inside it? | Explains the animations you will see |
| Can it be retriggered? | Explains why a feature sometimes extends |
| Are any figures stated for it? | Tells you what the studio publishes about it |
Seeing a feature in a free demo
Free demos are the easiest way to watch a feature without any money at stake, though you may need many spins before it appears. When it does, compare each step with your notes from the rules screen. For what a demo can and cannot tell you, read what a free-play mode can and cannot show.
Summary and further reading
Bonus features temporarily change a slot's rules, most often through free spins, multipliers, collection mechanics, hold-and-respin rounds or cascades. They concentrate the action and group outcomes, but they never change the odds of an individual spin. Read the rules first, then watch the feature in a demo. Our collections section groups games by shared traits, including simpler classic-style games with few or no features.
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Cascading Reels and Standard Reels Compared
How cascading reels differ from standard reels: what happens to winning symbols, how one spin can produce several wins, and what to look for in a paytable before trying either design.