Free spins
Rounds that cost nothing from the balance
A free spins round is where most of a modern slot keeps its return. The base game pays the small wins that keep a session going, and the round pays the ones the paytable is actually built around, which is why a session that never triggers it looks nothing like the published average.
Wild
Fills in for ordinary paying symbols
A wild takes the place of most ordinary symbols so a combination that lands one short still resolves. Scatters and bonus symbols are normally outside what it can copy, which is why it lifts everyday payouts but does nothing for the odds of reaching the feature round.
Scatter
Counts from any position on the field
Because the scatter ignores position, it is the one symbol whose odds do not change when the grid shape does. Games that expand the grid during a round therefore usually pay more per spin without triggering the bonus any more often.
Multiplier
Scales the payout it is attached to
Multipliers that reset every spin and multipliers that carry through a round are two different games wearing the same word. The carried kind is what turns a long bonus round into the outlier session players remember, and it is also why such rounds are rare.
Ante bet
Larger stake against a faster trigger
Switching the option on lifts the stake by a stated share, most often a quarter, and in return the feature round comes up more often. What it moves is how frequently the trigger arrives; what the round pays once it starts is unchanged.
Bonus buy
Buying straight into the feature round
Instead of waiting for scatters, a fixed multiple of the stake buys entry to the feature round outright, most often somewhere between 60x and 100x. Several regulated markets restrict or forbid the option, so whether the button exists at all depends on where the game is loaded.
Symbol collection
A meter fills with banked symbols
Nominated symbols are put aside in a meter as rounds go by, and hitting the stated mark opens a feature or hands over a prize. Whether the meter survives a closed session is a per title decision.
Respins
Part of the field spins once more
What is already on the field stays where it is while only the empty positions turn again, giving a near miss a second chance to resolve. Some titles hand out the respin for a combination that fell one symbol short, others for a specific symbol landing.
Jackpot
A prize pool outside the paytable
The jackpot is not part of the paytable and has a trigger of its own, commonly a symbol collection or a wheel. A fixed one always pays the same figure, while a progressive one grows out of a slice of every stake played until it is claimed.
Progressive free spins
The round strengthens as it runs
The round gets stronger the longer it lasts, with the counter or the symbol set improving at stated milestones. Rounds near the end of the sequence therefore carry more weight than the opening ones.