PROVABLY FAIR

COMMIT. RIP. REVEAL.

Before a pull, the server publishes its seed hash. After the seed is revealed, anyone can reproduce the exact rarity and card selection.

1. 01HMAC_SHA256key=serverSeed, msg=txSignature:cardIndex
2. 02ROLLfirst 13 hex chars ÷ 16^13
3. 03CARDfirst card whose cumulative odds exceed the roll (catalog order)

SELL-BACK Any vault card can be sold back within 3 days for 98% of its card value (2% fee), paid in that card's own xStock.