AutoplayA feature that spins the reels automatically for a set number of spins or until a condition (bonus triggered, bankroll dips, big win) is met. Operators in regulated jurisdictions sometimes disable or cap autoplay to slow down losses.Base gameThe regular spinning of the reels without bonus features active. The base game is usually a slow grind that funds the slot's real payout vector — the bonus round. Most slots return less than 50% of long-run RTP from base play alone.BTG (Big Time Gaming)Australian studio that invented and trademarked the Megaways mechanic (variable reel heights → variable ways to win, often 117,649 ways). Bonanza Megaways is the franchise; many other studios license the engine.Bonus buyA feature that lets the player pay a multiple of base bet (typically 50–500×) to skip directly to the bonus round. Common cost: 100× base bet on Pragmatic, 200–500× on NoLimit / Hacksaw flagships. Feature-buy RTP is usually 0.5–2pp lower than base-game RTP. See /games/slots/bonus-buy-math.Cap headroomThe hit multiplier as a percentage of the slot's theoretical max-win cap. A 25,000× hit on a 100,000× max-cap slot is 25% cap headroom. Most documented streamer hits land under 50%; the cap itself is reached far less than 1-in-10M spins.Cluster paysWin mechanic where symbols pay when 5+ of the same kind touch each other on the grid (orthogonally), regardless of payline position. Pragmatic's Sweet Bonanza popularised the mechanic — it's why "pays anywhere" looks chaotic but is just cluster detection.Free spinsThe headline bonus round on most slots. Usually triggered by 3+ scatter symbols in base game; gives a fixed number of spins with a multiplier or persistent feature active. Real RTP source for most slots — base-game grind funds the free-spins payout distribution.Hacksaw GamingMaltese studio (founded 2018) specialising in low-bet, high-volatility, max-win-cap-focused slots. Notable franchises: Wanted Dead or a Wild, Chaos Crew, Hand of Anubis, RIP City. Bonus buys central to product design; cap-x typically 10,000–100,000.Hit rateThe percentage of spins that pay anything at all (even a fraction of the bet). Provider-published; usually 20-35% on modern slots. Higher hit rate = more frequent small wins = lower variance = longer bankroll per $100.House edge100% minus RTP. The percentage of every dollar wagered the operator expects to keep over volume. A 96.5% RTP slot has a 3.5% house edge. Reduced-variant slots run 4–8% house edge.Live slotA live-dealer hybrid where a human host operates a physical wheel / reel / game-show format streamed over webcam — Crazy Time, Mega Wheel, Sweet Bonanza Candyland. Same math as RNG slots (theoretical RTP published) but with social atmosphere + variable host pacing.Max win / max-win capThe provider-defined upper limit on what a single spin (or sequence of base + bonus tumbles) can pay, expressed as a multiple of bet size. 5,000× = Pragmatic standard; 21,100× = Sweet Bonanza; 100,000× = NoLimit Mental; 300,000× = Tombstone R.I.P. (provider record holder).MegawaysBTG-patented mechanic with variable reel heights — instead of fixed 25 paylines, each reel shows 2–7 symbols per spin and "ways to win" = product of reel heights. Bonanza Megaways pioneered; many other studios license the engine for slots like Extra Chilli, Who Wants to Be a Millionaire Megaways, etc.Minimum betThe smallest stake the slot accepts per spin. Crypto-casino slots typically run $0.10–$0.20 minimums; some allow $0.01 micro-stakes. Lower minimum = longer bankroll exploration on a fixed deposit.MultiplierA value that multiplies a win by the listed factor. Multipliers can be base-game randomness (Sweet Bonanza scatter symbols), persistent stickies (Gates of Olympus tumbles), or progressive (Sticky Bandits xWays).NetEntSwedish studio (now Evolution-owned) — long history in modern slot design. Notable: Dead or Alive, Gonzo's Quest, Starburst, Divine Fortune progressives. Lower-volatility profile than NoLimit/Hacksaw; "legacy" feel.NoLimit CityStockholm studio specialising in extreme-volatility slots with proprietary mechanics: xWays (rolling reel heights), xNudge (nudging wilds), Infectious Wilds. Notable: San Quentin xWays, Tombstone R.I.P., Mental, Punk Toilet. Caps frequently 100,000×+; bonus rounds long and multiplier-rich.Paylines / ways to winThe patterns across reels that produce a winning combination. Classic slots had 1–25 fixed paylines; modern slots run 243 ways (every-reel-every-position) or 117,649 (Megaways). More ways doesn't mean better — total RTP is fixed regardless.Persistent multiplierA multiplier that increases by a fixed amount per win and stays through the entire bonus round. Mental, San Quentin xWays, and many NoLimit titles run this pattern — explains the long base-game grinds + monster final spins.Play'n GOSwedish studio (founded 2005) with deep catalog spanning low-vol classics through max-win adventures. Notable: Book of Dead franchise, Reactoonz, Rise of Olympus. Mid-volatility profile; clean math, reliable RTP transparency.Pragmatic PlayMaltese studio (founded 2015) — highest-volume releases in the streaming era. Sweet Bonanza, Gates of Olympus, Wolf Gold, The Dog House franchises anchor the catalog. Default mid-volatility, bonus-buy standard, broadest casino carriage.Progressive jackpotA jackpot that grows from a percentage of every wager across the network until someone hits it, then resets. Mega Moolah is the famous one (£1M+ jackpots routine). Counts toward the slot's total RTP but in a "1-in-50M shot" way — most sessions never see jackpot mechanics fire.Pseudo-random (PRNG)The RNG underlying every digital slot. Generates "random-looking" results deterministically from a seed. Modern crypto-casino slots publish seeds (via provably-fair scheme) so individual outcomes can be re-derived and verified after the fact.Push GamingBritish studio (founded 2010) — known for high-volatility math + clean modern aesthetics. Notable: Razor Shark, Mystery Museum, Razor Returns. Cap-x typically 5,000–20,000.Reduced-RTP variantA non-default RTP variant of a slot, picked by the operator. Same artwork, same mechanics, same max-win cap — but theoretical return reduced (e.g., 94% instead of 96.5%). The trap is that the slot looks identical to the headline version. Always check the in-game info panel.Relax GamingMalta-based studio (founded 2013). Operates as both a slot studio and an aggregation platform (Silver Bullet program). Notable: Money Train franchise (Money Train 1/2/3/4) — known for buy-feature ladders + persistent symbols.RTP (Return to Player)The percentage of every dollar wagered the slot pays back over infinite spins. Industry standard headline is 96.0–96.5%; legal floor in regulated jurisdictions is 88%. RTP describes the asymptote, not a session. See /games/slots/rtp-truth.Scatter symbolA symbol that pays regardless of payline position. Most scatters trigger the bonus round (free spins) when 3+ land on the reels. Distinguishing scatter from "regular paying symbol that pays anywhere" depends on the slot — read the in-game paytable.Sticky wildA wild symbol that locks in place for the rest of the spins. Famous in Dead or Alive 2 high-noon mode — sticky wilds create the persistent path to the max-win. Mental and Tombstone use sticky-wild-with-multiplier hybrids.Streamer favoriteEditorial flag on providers / slots — qualitative signal that a slot or studio appears in observable VOD frequency across the streamer scene. Not a popularity-score, more like "you'll recognize this when watching slot content."Tumble mechanicWinning symbols disappear and new symbols fall in to take their place, creating chains of wins from a single spin. Gates of Olympus and Sweet Bonanza popularised the mechanic. Each tumble can hit another multiplier, which is why these slots produce 1,000×+ hits from a $1 spin.Volatility / varianceHow spread out wins are. Low: small frequent wins, low variance per session. Very high: long base-game grinds + occasional huge bonus hits. Same RTP can play totally differently at different volatility profiles. NoLimit / Hacksaw flagships are very-high; Pragmatic flagships are mid.WildA symbol that substitutes for any regular symbol on a payline. Many slots have variants: sticky wilds (lock in place), expanding wilds (cover full reel), nudging wilds (move per spin), multiplier wilds (carry a multiplier).xWays / xNudge / xBombNoLimit City's proprietary mechanics. xWays = symbols that reveal as 2–3 stacked extras + a multiplier; xNudge = wilds that move 1 position per spin with a stacking multiplier; xBomb = symbol that explodes adjacent cells. Together they're why NoLimit slots have ~100,000× max-win caps.Yggdrasil GamingMaltese studio (founded 2013) — Nordic-themed catalog with deep franchises. Vikings Go Berzerk, Vikings Go to Hell, Holmes and the Stolen Stones. Slightly lower volatility than NoLimit/Hacksaw; consistent RTP transparency. 