Slot Glossary
34 terms covering Topo Mole's Tunnel Wilds, depth-based Mole Multipliers, Dig Bonus pick game, and the path to 3,000x.
Autoplay
Spin the reels automatically for a set number of rounds. Topo Mole lets you set stop conditions — stop when Underground Free Spins triggers, stop when the Dig Bonus opens, or stop on a single-win threshold. Useful for grinding the ~1 in 220 scatter trigger that opens the bonus.
Base Game
Standard play before Dig Bonus or Underground Free Spins triggers. Topo Mole's base game runs across 20 Lines on the 5×3 grid. Medium volatility means relatively steady drip wins — most session profit comes from Tunnel Wild events and the wait for scatter triggers.
Bonus Buy
Skip the base game and jump directly into Underground Free Spins. Topo Mole offers Bonus Buy at roughly 100x stake (RTP 96%). The buy maintains base RTP. UK and Netherlands block Bonus Buy by regulation.
Cascading Reels (Tumble)
Topo Mole doesn't use cascades. Wins resolve once per spin via 20 paylines. The replay action comes from Tunnel Wilds carving across rows or columns rather than removing winning symbols and dropping new ones. Different from cascade-driven slots like Sweet Bonanza or Reactoonz.
Dead Spin
A spin returning nothing. Topo Mole's medium volatility produces dead spins around 60-65% of base spins. Even dead spins occasionally show partial Tunnel Wild moves on non-winning lines for visual flavor.
Depth Counter
Topo Mole's Underground Free Spins mechanic. Each spin advances the depth meter by 1, raising the running multiplier. By spin 12 of a base round, the multiplier sits at x12. Retriggers don't reset the counter — they extend it past x20.
Dig Bonus
Topo Mole's pick-and-reveal mini-game. Triggered by 3 shovel symbols on the reels in the same spin. A grid of underground tiles opens — pick one at a time to reveal cash prizes (5x-250x stake), x2/x3 multiplier tiles, or extra picks. The round ends when you flip a rock tile.
Dig Bonus Strategy
Topo Mole's Dig Bonus weighting model. The math weights deeper-layer entry points toward the corners of the grid. Multiplier tiles tend to reveal mid-round rather than at the start, so resist cashing out early if the option appears. Average payout lands near 50x the stake.
Feature Trigger Rate
How often features activate. Topo Mole's Underground Free Spins triggers ~1 in 220 base spins. Dig Bonus triggers ~1 in 180. Combined, expect a feature event roughly every 100 spins on average.
Hit Frequency
How often a paying combination forms. Topo Mole's base hit rate sits around 30-35% — about 1 in 3 spins pays something. Standard for medium-volatility InOut Games designs. Tunnel Wilds boost effective win frequency because they convert dead-line spins into multi-line payouts when wilds intersect winning combinations.
Max Win
The absolute ceiling per round. Topo Mole caps at 3,000x — modest by 2025 standards but reachable through medium-vol design. The path runs through Underground Free Spins with a high depth multiplier (x18+) combined with Tunnel Wilds creating large winning combinations.
Megaways
A Big Time Gaming licensed mechanic with up to 117,649 ways. Topo Mole doesn't use Megaways — uses 20 Lines on a 5×3 grid. InOut Games' design philosophy keeps the grid simple while concentrating innovation in the Tunnel Wild and depth-multiplier mechanics.
Mole Multipliers
Topo Mole's headline depth-based multiplier system. Active during Underground Free Spins. Each spin advances the depth counter by 1, which raises the running multiplier. The multiplier resets only when the bonus closes — late-round wins are worth dramatically more than early ones.
Multiplier
A value that multiplies a payout. Topo Mole uses two multiplier types: Dig Bonus tiles (x2/x3 hidden multipliers that double or triple collected cash) and Mole Multipliers in Underground Free Spins (deterministic +1 per spin, peaking at x12 base or x20+ with retriggers).
Paylines
Predefined lines where matching symbols form a win. Topo Mole runs 20 Lines on a 5×3 grid. Lines pay left-to-right starting from reel 1. All 20 lines are always active — you can't reduce the count to lower the stake. Standard for modern InOut Games 5×3 layouts.
Paytable
Reference chart for symbol payouts. Access through the in-game info menu. Topo Mole's premium symbols (mole character, gold nugget) pay the most. Mid-tier covers digging tools (lantern, helmet, pickaxe). Card royals (A/K/Q/J/10) fill the bottom across the 20-line layout.
Pick-and-Reveal Mini-Game
Topo Mole's Dig Bonus structure. Pick tiles one at a time from a grid of underground layers. Each layer drills deeper with bigger values. Hidden multiplier tiles can double or triple collected cash mid-round. The rock tile is the closer — flip it and the round ends.
Retrigger Mechanic
Topo Mole's Underground Free Spins extension. Land 2+ scatters during the bonus and 6 additional spins are added. The depth meter doesn't reset — it continues climbing, pushing Mole Multipliers past x20 in chained-retrigger rounds. Retrigger probability sits around 14% per spin.
RNG (Random Number Generator)
The certified algorithm determining every spin outcome. InOut Games uses GLI-tested RNGs — independently audited for fairness in regulated markets. Each spin in Topo Mole is independent of the last; previous Tunnel Wild positions or scatter counts have zero predictive value for future spins.
RTP (Return to Player)
The theoretical percentage of wagered money the slot returns over millions of spins. Topo Mole runs at exactly 96% — matching the industry standard. InOut Games certifies this figure through independent testing for the standard configuration. Some operators may run lower variants (94-96% common) — verify in the game info screen.
Scatter
A symbol that triggers features regardless of payline position. Topo Mole uses two scatter types: shovel symbols (3+ trigger Dig Bonus) and bonus scatters (3+ trigger Underground Free Spins). Each trigger path is independent — landing both scatter types together is rare.
Session Variance
The gap between actual results and theoretical RTP. Topo Mole has 96% RTP, but a 200-spin session can return 50% to 200% of your wager. Medium volatility means session swings are smaller than high-vol slots — sessions tend to land within 70-150% of theoretical RTP without dramatic outliers.
Shovel Symbol
Topo Mole's Dig Bonus trigger. Three shovel symbols anywhere on the reels open the pick-and-reveal screen. Different from the bonus scatter that triggers Underground Free Spins. Two distinct symbol types create two distinct trigger paths.
Stake
Your bet per spin. Topo Mole ranges from $0.10 to $50. The stake applies uniformly across all 20 paylines — no per-line bet. All payout values (Dig Bonus tiles, Mole Multipliers, max win) are quoted as multiples of stake.
Sticky Wild
A Wild that stays in place across multiple spins. Topo Mole's Tunnel Wilds are NOT sticky — they appear within a single spin and disappear with the next. The persistence comes from the Underground Free Spins depth counter rather than from sticky wild positioning.
Tunnel Wilds
Topo Mole's headline mechanic. When a mole wild lands, it carves a path across one row or column, dropping Wild markers on every position it passes through. Multiple tunnels in the same spin can intersect, blanketing large sections of the 5×3 grid with Wilds.
Tunnel Branching
Topo Mole's Underground Free Spins tunnel variant. In the base game, tunnels run in one direction. During Underground Free Spins they can curve, branching across rows and columns from a single mole landing. The branching geometry produces wider multi-line coverage than base-game tunnels.
Underground Free Spins
Topo Mole's main bonus round. Triggered by 3+ scatters. Awards 12 spins by default (4 scatters award 18, 5 scatters award 24). Each spin advances the depth counter and Mole Multiplier. Tunnel Wilds spawn at higher rates and can branch instead of running straight.
Volatility (Variance)
How payouts are distributed. Topo Mole is rated Medium — relatively steady wins with occasional spikes from Tunnel Wild events and depth-stacked Underground Free Spins runs. Good for longer sessions where you want manageable bankroll variance without dramatic swings.
Ways to Win
An alternative to fixed paylines. Topo Mole uses 20 Lines, not ways-to-win. The 20-line layout works well with Tunnel Wild mechanics because the wilds carve patterns that intersect multiple specific lines rather than creating dynamic cluster groups.
Wild
A symbol that substitutes for any regular symbol to complete combinations. Topo Mole's mole wild substitutes for everything except scatters and shovel symbols. The wild's special trick is the tunnel mechanic — it doesn't just sit on one position, it carves a path across the row or column.
Win Distribution
How total payouts spread across categories. Topo Mole's medium-volatility split: Underground Free Spins ~35% of total RTP, Dig Bonus ~20%, base-game Tunnel Wild events ~30%, standard payline wins ~15%. The distribution is more balanced than high-vol slots.
InOut Games Provider Catalog
InOut Games is an arcade-slot studio focused on single-mechanic hooks per release. Topo Mole (2025) sits in their digging-themed catalog alongside titles like Ise Fishing and Tawer Rush. GLI certification covers all titles. Distribution skews LatAm and select European regulated markets.
5×3 Grid with 20 Paylines
Topo Mole's grid format. 5 reels × 3 rows = 15 cells. Pays through 20 Lines fixed paylines — moderate density. The 5×3 layout is the most common slot format. InOut Games' design keeps the grid simple while concentrating innovation in the Tunnel Wild mechanic and depth-driven free spins.
See These Terms in Action
Try Topo Mole demo and watch Tunnel Wilds carve across the grid, the depth counter climb during Underground Free Spins, and Dig Bonus tiles reveal hidden multipliers.
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