1) Introduction

Classic Keno is the baseline against which every other keno variant is compared. The mechanism is simple: you choose a set of numbers from 1 to 80, the game draws 20 numbers without replacement, and you get paid if enough of your picks appear in the draw according to a published paytable. There are no multipliers, no free games, and no thematic overlays—just the core combinatorics that define the hit distribution. Because it is transparent and modular, Classic Keno is ideal for learning fundamentals: probability of hits, expected value (EV), variance, bankroll sizing, and session risk.

This chapter formalizes the rules, presents representative paytables, and derives the math step by step. It then converts the math into practical strategy guidance, including spot-count selection and bankroll policy for typical goals such as long play, moderate volatility, or targeted high-risk, high-reward sessions. To anchor abstractions to outcomes, we include simulated long-run results and short session case studies. Graph placeholders are provided for hit distributions, payout-frequency histograms, RTP by spot count, and drawdown profiles so you can insert generated charts later without changing the document structure.

Use this chapter as your canonical reference. When you evaluate more complex variants like Cleopatra, Caveman, Power, Lightning, Fireball, or DaVinci, the same analytical scaffolding applies. You will swap the paytable and bonus terms, but the combinatorial spine remains the same.

2) Rules & Gameplay

2.1 Core Rules

• Board: Numbers 1–80.
• Draws per round: 20 unique numbers sampled without replacement.
• Your selection (“spots”): Choose up to a maximum supported by the venue; 1–10 spots are standard for analysis, though some paytables extend to 15 or 20.
• Win condition: Payouts are based on how many of your chosen spots appear in the 20 drawn numbers. The mapping from hits to payout is defined by the paytable.
• Stake: A base wager per round (e.g., $1). Many implementations support multi-ticket or multi-credit bets.
• No bonuses: Classic Keno has no multipliers, free games, or wilds. That makes its math clean and its variance profile predictable.

2.2 Round Walk-Through

1. You choose a spot count, say 6 spots, then mark six numbers (e.g., 3, 8, 19, 27, 55, 74).
2. You place a stake (e.g., 1 credit).
3. The game randomly draws 20 distinct numbers from the 80-number pool.
4. Count how many of your six picks appear among the 20 drawn numbers (the number of “hits”).
5. Consult the 6-spot paytable to determine the payout for that number of hits. Zero through one hit typically pays 0, two or three might return small prizes, and higher hits escalate.
6. Net result = payout minus stake.

2.3 Design Implications

Since Classic Keno lacks multipliers and special triggers, the only levers that alter return and feel are the paytable and your spot count. The paytable determines expected value and relative rewards for each hit tier. The spot count determines your hit distribution’s shape: low-spot games hit small returns often but cap the upside; high-spot games hit rarely but can deliver large wins. Balancing these choices is the essence of Classic Keno strategy.

3) Paytables

Paytables vary by jurisdiction and operator. Below are representative, pedagogical examples. They are not universal or prescriptive. Always plug the actual paytable into the formulas to get precise RTP and volatility.

3.1 Example 4-Spot Paytable

Notes: 4-spot is a popular “quick-hit” choice. Returns cluster around 0–2 hits with occasional 3s and rare 4s.

3.2 Example 6-Spot Paytable

Notes: The 6-spot adds a real top-end while keeping occasional small returns at 3 or 4 hits.

3.3 Example 8-Spot Paytable

Notes: High top prize. Rare event frequency. Variance increases.

3.4 Example 10-Spot Paytable

Notes: 10-spot emphasizes long-odds jackpots. Bankroll swings are significant.

3.5 Practical Use

• To compute expected return, multiply each hit probability by its payout and sum over all hit tiers, then divide by stake.
• To compare spot counts, chart RTP and variance for the paytables you plan to use and select based on session goals.

4) Mathematics of Classic Keno

4.1 Hit Probability

Let n be the number of spots you choose. Let k be the number of hits in a draw of 20 numbers from 80. The probability of exactly k hits is hypergeometric:

P(K = k) = [C(n, k) * C(80 - n, 20 - k)] / C(80, 20)

where C(a, b) is the binomial coefficient “a choose b”. This distribution defines the entire game: once you know P(K=k) and the paytable pay(k), you can compute expectation and variance.

4.2 Expected Value (RTP)

EV_per_credit = Σ_k P(K=k) * pay(k)

If the stake per round is 1 credit, the expected return (RTP) is the same as EV per credit. If the stake is s, then EV in credits times s gives currency units. House edge equals 1 − RTP.

4.3 Variance and Volatility

Var = Σ_k P(K=k) * [pay(k)]^2 − [EV]^2

Volatility grows with spot count when top-end payouts escalate faster than the gain in mid-tier hit frequency. For small-spot games, you see frequent small returns; for large-spot games, long sequences of losses punctuated by rare peaks.

4.4 Tail Behavior

For higher spot counts, the right tail (large k) is extremely thin. For example, in a 10-spot game, hitting 9 or 10 is astronomically rare. Operators shape paytables to keep RTP in target while distributing reward between mid-tier consistency and right-tail jackpots.

4.5 Worked Example: 6-Spot EV (Illustrative)

Using the example 6-spot paytable above, compute P(K=k) for k = 0..6, multiply by the payouts, and sum. The exercise shows how top-end prizes contribute outsized variance relative to their probability mass.

5) Graphs & Charts

The following figures are placeholders. Generate the images with your simulator or analytics tool and upload them to your media library. The <img src> paths can be updated to the final URLs without changing the narrative text.

6) Strategy Insights

6.1 Define the Objective

• Time on device: Favor lower spot counts and paytables with modest mid-tier pays. Target stability over peaks.
• Moderate swings, occasional peaks: 6–8 spots with balanced mid-tier pays keep you engaged while allowing real upside.
• Jackpot hunting: 9–10 spots with steep top payouts. Accept long droughts.

6.2 Spot Count Selection

The spot count moves the entire distribution. One to four spots compress outcomes near small hits and misses. Five to eight spots widen the distribution. Nine to ten spots prioritize extreme outcomes. Your bankroll and tolerance for cold streaks should dictate the selection more than superstition about “lucky counts.”

6.3 Bankroll Management

• Unit size: Keep a base unit that yields at least 150–300 rounds at your target volatility. Increase unit size only if variance remains tolerable.
• Loss limits: Pre-commit to a maximum session drawdown. Stop if reached. Keno’s independence makes “chasing” irrational.
• Win locks: If a top-tier hit occurs, define a policy to lock a portion and continue with a smaller unit.

6.4 Paytable Sensitivity

Two paytables with identical RTP can feel different. Shifting weight from mid-tiers to the top prize increases variance for the same expected value. Choose the feel you want. For analytics, compute not just EV but also variance and a dispersion metric such as coefficient of variation (CV).

6.5 Myths to Ignore

• Recent draws predict next results: False. Draws are independent and without replacement within a round only.
• Number hotness: Irrelevant under fair RNG and uniform selection.
• Pattern shapes: Cosmetic. EV depends on paytable and hit probabilities.

6.6 Practical Templates

• Low-variance session: 4-spot, 1 credit, 300 rounds. Expect frequent small returns, rare 4-hit spikes.
• Balanced session: 6-spot, 1 credit, 250 rounds. Occasional mid-tier hits with visible peaks.
• High-variance hunt: 8–10 spots, 1 credit, 200 rounds. Potentially many losses, compensated by tail rewards if struck.

7) Simulation Results

Simulations connect theory to empirical behavior. Below we describe typical outcomes when running fair draws with the example paytables. Replace the narrative with your own measured metrics once you run your simulator at scale. Always report seeds, number of rounds, and confidence intervals.

7.1 Methodology

• Independent trials of 100,000 to 1,000,000 rounds per spot count.
• Uniform RNG over combinations of 20 draws from 80 per round.
• Payouts resolved via the specified paytable for each configuration.
• Metrics: RTP estimate, standard error, variance, 1%/5% drawdown quantiles, hit-frequency table, and time-to-event for each paying tier.

7.2 Typical Findings (Descriptive)

• RTP stability: Estimate converges near the theoretical EV by ~500k rounds. Under 100k, noise is visible in high-tail games.
• Volatility vs spots: As spot count rises, the loss streak distribution lengthens. Mid-tiers in 6–8 spots help punctuate runs.
• Right-tail scarcity: Top-tier hits happen in the extreme percentiles of time-to-event. Bankrolls must anticipate long waits.
• Drawdowns: Even at identical RTP, drawdown depth varies with paytable shape. More weight on the top prize widens drawdown tails.

7.3 Example Output Tables (Placeholders)

8) Case Studies

8.1 Low-Variance Entertainment (4-Spot, 300 Rounds)

A player brings a 300-credit bankroll with a 1-credit unit. They choose a 4-spot paytable with modest 2- and 3-hit pays. Over 300 rounds, they see frequent non-paying outcomes but enough 2-hit returns to slow the slide. Occasional 3-hit pays create psychological reinforcement. The rare 4-hit spike defines the session high. The player’s perceived control comes from steady cadence, not from predicting numbers.

8.2 Balanced Risk (6-Spot, 250 Rounds)

With 250 credits and a 1-credit unit, the player picks 6 spots to chase occasional mid-tier hits. The mode of 2–3 hits generates many dead rounds, but 4-hit pays inject momentum. A 5-hit result is memorable and often defines the session. The 6-hit is a statistical outlier in the short run; the player should not plan around it. This profile suits players who want real peaks but can tolerate lulls.

8.3 High-Variance Hunt (8–10 Spots, 200 Rounds)

A jackpot-oriented player brings 200 credits. They target 8–10 spots with aggressive top-end pays. The baseline is many non-paying rounds. The session outcome hinges on striking a rare 6+ hit for 8-spot or a 7+ for 10-spot. If the tail fails to materialize, the loss is steep. If it triggers, the session flips from red to green quickly. This style is statistical cliff-walking by design.

8.4 House Edge vs Experience

Two players can face the same RTP yet report different satisfaction because paytable shape changes the path to expectation. One player prefers frequent small validations. Another accepts droughts for a shot at large peaks. Classic Keno lets you choose the path by picking spot count and paytable combination that produces the session shape you prefer.

9) FAQ: Practical Questions

9.1 Do patterns on the board matter?

No. Under uniform random draws, spatial patterns are cosmetic. Only your spot count and the paytable matter for EV and volatility.

9.2 Are past rounds predictive?

No. Each round is independent. The sample without replacement applies within a single round only.

9.3 Is there an optimal spot count?

Optimal for what? For longer time on device, favor lower spots with supportive mid-tiers. For jackpot exposure, favor higher spots. EV depends on the paytable, not on the spot count alone.

9.4 How large should my bankroll be?

Enough to absorb expected drawdowns for your chosen volatility. As a rule of thumb, target 150–300 rounds at your base unit, then adjust after testing the variance feel.

10) Summary & Takeaways

• Classic Keno is defined by a hypergeometric hit distribution and a paytable. No bonuses means clean math.
• Spot count shapes variance. Paytable shape distributes return across mid-tiers vs tail prizes.
• RTP equality does not imply equal experience. Choose the feel you want, not just the mean.
• Bankroll and unit sizing dominate short-run outcomes. Policy beats “prediction.”
• Use simulations to validate the math for your exact paytable before committing to a session plan.