Megaways has become the most commercially successful slot mechanic of the past decade. Originally patented by Big Time Gaming, it has been licensed to over 20 studios and generated billions in GGR worldwide. But how exactly does it work? And what does building a Megaways-licensed slot actually require from a development perspective? At True North Devs — which obtained a Megaways engine license in 2024 — we've worked through every layer of the implementation. This is what we learned.
The Core Concept: Variable Reels
Traditional video slots use a fixed grid — 5 reels, 3 rows, 20 paylines. Megaways replaces the fixed row count with a dynamic one. On each spin, every reel independently randomises how many symbols it displays — typically between 2 and 7. This means a 6-reel Megaways game can display anywhere from 64 ways (2×2×2×2×2×2) to 117,649 ways (7×7×7×7×7×7) on a single spin.
The way count is shown prominently in the UI — a number that changes dramatically on every spin — and this variability is a core psychological driver of the mechanic's appeal. A spin that delivers 117,649 ways feels fundamentally different from one delivering 512 ways, even if the underlying RNG outcome is the same.
The Mathematics of Way Counts
Ways-to-win are calculated by multiplying the number of symbols visible on each consecutive reel that contains matching symbols, starting from the leftmost reel. Unlike paylines, you don't need symbols on a specific row — any position on any reel counts. This means the maximum win potential scales non-linearly with reel height. A 7-high reel contributes 7× to the win multiplier for that symbol, versus only 2× for a 2-high reel.
This creates a natural interaction between the randomised reel height and the cascade/avalanche mechanics that most Megaways games include. When winning symbols are removed and replaced by new ones falling from above, the reel height remains constant — creating the possibility of multiple consecutive wins on a single base spin that far exceed the initial stake.
Cascade Multipliers: The Key Driver of Variance
Most Megaways implementations include a cascade multiplier that increments with each consecutive win within a spin. A typical structure might be: first cascade = 1×, second = 2×, third = 3×, and so on up to a cap (commonly 15× or unlimited during free spins). The interaction between unlimited way counts, cascade chains, and an escalating multiplier is what produces the "life-changing win" potential that drives Megaways's commercial appeal — and its notoriously extreme volatility.
Free Spins: Where the Real Math Lives
In most Megaways games, the free spins feature contributes 40–60% of total RTP. This is because the multiplier is typically retained across spins (not reset to 1× after each spin as in the base game). A free spins round where the multiplier climbs to 15× or 20× before a big Megaways landing can produce individual spin payouts of 1,000× to 5,000× stake — events that might occur once every 50,000–200,000 spins but account for a disproportionate share of total payout.
Designing the free spins trigger frequency, minimum spin count, and multiplier ceiling requires careful simulation to hit the target RTP while delivering a volatility profile that the operator's player base can sustain. Too high volatility and you'll see player balance erosion complaints; too low and the game feels like a poor Megaways imitation.
Implementation Requirements for Licensees
Obtaining a Megaways license from Big Time Gaming comes with specific technical requirements around the RNG implementation, symbol weighting logic, and UI presentation of the way count. The way count must be calculated and displayed in real time, derived directly from the RNG output — it cannot be a post-hoc presentation of a predetermined outcome. This has implications for server-side outcome generation and the client-server communication protocol.
Performance Considerations
Rendering a variable-height grid that changes every spin, combined with cascade animations and a live way-count display, creates real performance challenges on mid-range mobile devices. We solved this by pre-rendering symbol strip variations at build time, using a CSS grid with dynamic row assignments, and batching the cascade animation queue into a single rAF cycle. The result: smooth 58fps cascade sequences on a Samsung Galaxy A52 — our target baseline device.
If you're planning a Megaways-licensed title and want to discuss implementation or math model design, our team is here to help.