d20 Law of Large Numbers

Watch how chaotic a small sample looks — and how many rolls it actually takes to stabilize.

Total Rolls
0
Most Rolled
Least Rolled
observed frequency
true probability (5%)
Still chaotic at 100 rolls. A typical 3–4 hour session produces 15–40 d20 rolls per player. The Law of Large Numbers needs far more than that to flatten the curve.
Math GM — Roll with Intention