Global Bitcoin Summit — Entropy Dice Mockup

Why This Matters — The Coldcard Incident (July 2025)

A firmware bug in Coldcard 4.0.0 (March 2021) caused devices to skip the hardware RNG and fall back to predictable software entropy. Result: 594 BTC (~$38M) swept in 25 minutes. The fix: add your own physical randomness via dice rolls. If a user enters 99 d6 rolls during seed generation, even a fully compromised device cannot produce a guessable key. These dice are the tool.

Entropy Specifications

Die Type

Standard 6-sided cube. The correct format for Coldcard, SeedSigner, Jade, and Foundation Passport dice entropy input.

Rolls Required

log₂(6) ≈ 2.585 bits per roll × 99 rolls = ~256 bits. Minimum for a secure 24-word BIP39 seed phrase.

256

Bits of Entropy

The world's fastest supercomputer would take longer than the age of the universe to brute-force. This is the standard.

19mm

Recommended Size

Casino-grade size. Large enough to read fast, packs neatly alongside a hardware wallet.

2–3

Dice Per Pack

Roll 2–3 simultaneously — halves the time to reach 99 results. Good for live event demos.

GBS

Event Branding

Global Bitcoin Summit starburst on Face 1. Given to attendees at the October event as a functional keepsake.

🎨 Face Layout

Face 1: GBS starburst network icon + "Global Bitcoin Summit" + "Human Rights Foundation" micro text — replaces the standard single-pip face
Faces 2–6: Classic pip arrangement, Bitcoin orange (#F7931A) pips on matte black
Corner registration numbers in small mono font on each face
Optional: Face 6 with "99 ROLLS" or "256 BITS" micro engraving below the six pips

🏭 Manufacturing

Casino-grade precision dice, sharp corners, balanced weight — not toy dice
Vendors: Dice Envy, Chessex custom, or any casino dice manufacturer (min run ~100–500 units)
Material: Cellulose acetate or acrylic — both work. Avoid hollow plastic
Pips: Inlaid + filled with colored resin, not painted (paint wears off)
Logo face: laser engraved or pad-printed on the face

📦 Packaging

Matte black card sleeve or small rigid box
Inside lid: "99 Rolls. 256 Bits. Your Keys."
Include a small tally card for tracking 99 rolls during setup
QR code → GBS entropy guide or Coldcard paranoid mode docs
Bundle of 2 dice so multiple can be rolled simultaneously

✅ Hardware Wallet Compatibility

Coldcard Mk4 / Q: Advanced → Dice Roll Seed — enter each roll, device adds to hardware entropy
SeedSigner: Native dice roll seed generation, d6 supported natively
Jade (Blockstream): Dice entropy input supported
Foundation Passport: Supports dice seed generation
Works with any BIP39-compliant wallet with dice entropy support

Custom Entropy Dice

Why This Matters — The Coldcard Incident (July 2025)

🎨 Face Layout

🏭 Manufacturing

📦 Packaging

✅ Hardware Wallet Compatibility