How it works
How a Bitcoin block hash becomes a universe
Bitcoin seals a new block roughly every ten minutes, and the whole world sees the same new hash at the same moment. That hash is 32 bytes that nobody chose and that cost real work to produce. BTCBANG reads those bytes as the physical constants of a universe and runs that universe from its first instant to heat death, with exactly the engine, the NFT contract and the token that BNBBANG uses. This page explains each step and what is different when the singularity is a Bitcoin block.
1. Thirty-two bytes the whole world watched being made
A Bitcoin block hash is the double SHA-256 (SHA-256d) of the block header. It is 32 bytes, the same shape as a BNB Chain block hash. It is fixed the moment the block is found, it is public on every node and every explorer, and no single party controls what it looks like: miners can only search for a hash below the target, they cannot pick its bytes. That is exactly what you want from a source of universes. The same hash always produces the same universe (determinism), nobody can order a nicer one (no selection), and, unlike a BNB block, every Bitcoin block carries proof of work that anyone can check.
One block every ten minutes means one new universe every ten minutes, and everyone on the planet is looking at the same one. The simulator takes a block by latest, genesis, random, a height you type, or a hash you paste. Any height at or below the current tip can be detonated, including the block that was just mined. It does not search by date; if you want the block from a day that matters to you, look up that day's height on mempool.space and paste the height. A pasted hash is checked against Bitcoin mainnet first; a hash that is not a mainnet block is refused rather than silently replaced.
2. The same derivation as BNBBANG, byte for byte
The seed is the Bitcoin block hash itself, with no second transform. From it the engine draws one slot per parameter with keccak256, exactly as it does for a BNB block:
u_i = uint256(keccak256(btcHash ‖ uint8(i))) mod 1e9 one slot per parameter, i = 0, 1, 2 …
tier = uint256(keccak256(btcHash ‖ uint8(255))) mod 1000 how far the constants stray from oursEverything after that (the tier table, the string-gas dimension draw, the 23 parameters, the outcome, the grade, the cardHash, derivation version 3 and card shape 3) is the same code, in the same order, with the same constants. The derivation is integer-only and open source (bnbbang-engine), so a Bitcoin universe and a BNB universe are values of one function. Nothing is tuned for Bitcoin.
Leading zeros do not matter. A current Bitcoin hash starts with about nineteen hexadecimal zeros, because that is what the difficulty target requires. That structure disappears at the keccak step: the output of keccak256 over the hash plus a slot byte is uniform whatever the input looks like, so the tiers, the twelve endings and the five grades come out with the same shares as they do for BNB blocks. The number of leading zeros is printed on the card as a piece of information (the block's own proof of work), but it does not touch the physics.
The parameter table, ranges and references live in engine/params.js of the engine repository. The same code runs in your browser, on the server, and in the verification tool.
3. Running the universe
With the constants fixed, the engine walks the standard sequence and asks a yes/no question at each stage:
- Inflation and geometry. Does space end up with three large dimensions? With D ≥ 4 there are no stable orbits and no stable atoms; with D ≤ 2 there is no Newtonian attraction.
- Expansion history. Does the universe recollapse (Big Crunch), tear itself apart, or expand forever?
- Nucleosynthesis and atoms. Do protons survive, do electrons bind, do nuclei form?
- Structure. Are the primordial fluctuations large enough to grow galaxies, but not so large that everything collapses into black holes first?
- Stars. Is there a mass window in which fusion ignites, and do stars live long enough?
- Chemistry. Does the triple-alpha process produce carbon and oxygen; is there a liquid-water window?
- Time. Is there enough of it, before heat death, for observers to appear?
The first "no" ends the run and names the outcome. The whole run takes milliseconds, so the card for a block that was mined a minute ago is ready as soon as the hash reaches the site.
4. The twelve endings
Every universe gets exactly one of these verdicts. The list matches the contract's outcomeName() one-to-one and is identical for Bitcoin and BNB blocks. Examples are generated by the same engine; rather than reading about them, type any Bitcoin height into the simulator and watch the run.
| Outcome | Name | What happened |
|---|---|---|
| 0 | Unstable orbits | Space did not settle into three dimensions. Orbits and atomic ground states are unstable; matter oscillates between collapse and escape. By far the most common ending. |
| 1 | Big Crunch | Expansion stops and reverses. Everything is compressed back into a point before anything interesting has time to happen. |
| 2 | Big Rip | Phantom dark energy (w < −1) tears structures apart. Not reachable with the current parameter ranges; kept so the contract's outcome list stays complete. |
| 3 | Heat death, no structure | An almost perfectly uniform gas that only dilutes and cools. Fluctuations were too small for anything to clump. |
| 4 | Black hole dominated | Fluctuations were too large. Clumps collapse into horizons before they can cool into galaxies. |
| 5 | No atoms | No baryons, or protons decay, or electron shells cannot bind. Light and particles, but nothing that holds together. |
| 6 | No chemistry | Atoms and light exist, but there is no carbon, no hydrogen, or no rigid molecules. Nothing to build with. |
| 7 | No stars | Galaxies form, but no star ever ignites: the fusion mass window is empty. |
| 8 | Stars but no life | Stars, planets and chemistry are all there, but there is not enough time, or not enough of a stage, before the lights go out. |
| 9 | Observers possible | Galaxies, stars, planets and chemistry are all present, and there is enough time. The rare one, and the only grade S. |
| 10 | No carbon chemistry | Stars and chemistry exist, but the triple-alpha process cannot make carbon or oxygen, or there is no liquid-water window. |
| 11 | Beyond model (D≠3) | The dimension came out fractional or otherwise off three. The nucleosynthesis, star and chemistry formulas only hold for D = 3, so the remaining numbers are extrapolations, and the engine says so. |
Because the keccak step erases everything about the input, the shape of the distribution is the one measured on BNB blocks: more than nine in ten universes never get past their first second, and a few percent grow something that could look back. The random-sample table is on bnbbang.com; you can repeat the draw on Bitcoin heights with the engine and count for yourself.
5. Grades
The grade is decided by the outcome and the dimension only. It does not change the mint reward: every mint issues the same amount of BANG, so there is nothing to gain by scanning for a grade. Badges (section 7) do not change the grade either.
| Grade | Rule |
|---|---|
| S | Observers possible |
| A | Exactly three spatial dimensions, but observers are not possible |
| B | Another integer dimension (2, 4, 5 …) |
| C | A fractional dimension |
| D | Dimension of one or less, or no dimension could be derived |
6. Six confirmations before minting, and why
You can look at any block the moment it exists, including the newest one. Minting is different. The site will only sign a mint for a Bitcoin block once it has six confirmations, which takes about an hour.
The reason is reorganisation. A block that was just found can still be replaced if another chain of blocks overtakes it; when that happens its hash disappears from the main chain and a different block takes that height. A different hash is a different universe. If a mint had already gone through for the old hash, the NFT would point at a block that Bitcoin no longer recognises: an orphan universe. Six confirmations is the customary depth at which that stops being a practical concern, so the birth certificate is stamped only then.
Until then the card can be viewed and detonated into 3D, the mint button is greyed out, and the card shows how many confirmations are still missing together with a countdown. When the count reaches six, minting opens and the first confirmed transaction owns the block. Nothing about the universe changes while you wait: the hash is already fixed, so the constants and the ending are already fixed.
7. Badges: a second layer, not a second physics
Physical rarity (S to D) looks only at the hash. On top of that, a Bitcoin block has a history, and some heights are famous. BTCBANG marks those with badges printed on the card. Every badge can be computed from the height or has a public source; none of them touches the derivation, the outcome, the grade or the mint reward.
| Badge | Rule | Blocks |
|---|---|---|
| Genesis | Height 0, mined 2009-01-03 | 1 |
| Halving | height % 210000 == 0 and height > 0: #210,000, #420,000, #630,000, #840,000 | 4 |
| Difficulty period | height % 2016 == 0, the first block of each difficulty period (height 0 included) | ≈480 |
| Famous | Curated list, may be extended: six blocks with a documented place in Bitcoin's history | 6 |
The eleven badge blocks named in the launch specification, with the hashes the site's self-test checks them against:
| Height | Why it matters | Block hash |
|---|---|---|
| 0 | Genesis block (also the first block of the first difficulty period) | 000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f |
| 1 | The first block ever mined after genesis | 00000000839a8e6886ab5951d76f411475428afc90947ee320161bbf18eb6048 |
| 170 | The first bitcoin transfer between two people, Satoshi to Hal Finney | 00000000d1145790a8694403d4063f323d499e655c83426834d4ce2f8dd4a2ee |
| 57,043 | The pizza block: the first recorded purchase of goods with bitcoin | 00000000152340ca42227603908689183edc47355204e7aca59383b0aaac1fd8 |
| 74,638 | The value-overflow incident, later removed by a chain rollback and fix | 000000000069e1affe7161ab4bcbeacebb4ddf155b50e807f42de971b688a09b |
| 210,000 | First halving | 000000000000048b95347e83192f69cf0366076336c639f9b7228e9ba171342e |
| 420,000 | Second halving | 000000000000000002cce816c0ab2c5c269cb081896b7dcb34b8422d6b74ffa1 |
| 481,824 | SegWit activation | 0000000000000000001c8018d9cb3b742ef25114f27563e3fc4a1902167f9893 |
| 630,000 | Third halving | 000000000000000000024bead8df69990852c202db0e0097c1a12ea637d7e96d |
| 709,632 | Taproot activation | 0000000000000000000687bca986194dc2c1f949318629b44bb54ec0a94d8244 |
| 840,000 | Fourth halving | 0000000000000000000320283a032748cef8227873ff4872689bf23f1cda83a5 |
Notice how few leading zeros the early hashes have (eight for block #1) compared with the recent ones: difficulty grew, the hashes got smaller, and the physics did not notice. The genesis block and the four halving blocks are held back from minting until an announced opening time, first come first served, with the team and related addresses excluded; the FAQ has the details.
8. One magazine, two fuses
BTCBANG does not issue a new token, does not deploy a new contract and does not open a new pool. It is a second fuse on the same magazine. A Bitcoin universe is minted into the same MirrorUniverse contract on BNB Smart Chain as a BNB universe, with the Bitcoin hash as blockHash and the Bitcoin height as blockNumber, and it pays out the same BangToken from the same mint-reward pool under the same rules.
| BNBBANG (bnbbang.com) | BTCBANG (bang.satloot.com) | |
|---|---|---|
| Singularity | BNB Chain blocks: over 120 million, about 29,000 a day, one every three seconds | Bitcoin mainnet blocks: about 966,000 in September 2026, 144 a day, one every ten minutes |
| NFT contract | MirrorUniverse | the same one |
| Token | BangToken (BANG) | the same one |
| Hard cap | 1,707,000 universes | the same counter, shared |
| Free phase | first 1,000,000 mints, no mint fee, 50 BANG each, 10 per address | shared: an address gets 10 free mints across both sites combined |
| Paid phase | 0.01 BNB → NFT + 600 BANG | the same |
| Market, names, rescue, Crafted | MirrorMarket, BangNames, intervention, MirrorCrafted | the same contracts; each site's market page shows the other's universes |
| Referral | tier-1 10%, tier-2 5%, paid after human review | the same codes, valid across both sites |
Scarcity was never in the singularity. BNB Chain produces more new blocks in an hour than could ever be minted, and Bitcoin has produced fewer than a million blocks in its whole life. The only finite thing is the magazine: 1,707,000 slots, and both sites draw from it. Bitcoin has far fewer singularities, but each one is a real block with proof of work that the whole world saw at once, which is why BTCBANG can promise a rhythm: a new universe every ten minutes, open to minting an hour later, and whoever mints first keeps it.
9. What the chain can and cannot see
At mint time the NFT contract compares the submitted hash with blockhash(blockNumber) on BNB Smart Chain and records the result in a verified flag. BSC has no way to look at Bitcoin, so for every Bitcoin universe that flag is false. This is the normal state, not an error, and the contract records it without reverting. The mint itself is signed by the server only after it has fetched the hash for that height from Bitcoin and counted six confirmations.
Whether an NFT is a Bitcoin universe or a BNB universe is decided by the pair (blockHash, blockNumber) stored with it. Take the blockNumber to any Bitcoin node or explorer: if the hash at that height equals blockHash, it is a Bitcoin universe; otherwise check the same pair on BSC. Anyone can do that with no help from this site, and the verification page walks through it step by step, including recomputing the constants, the ending and the cardHash from the hash alone.
10. One hash, one universe, one owner
Detonating is free and happens off-chain; no wallet is needed to look. If you want to keep a universe, you mint it: the NFT contract stores tokenOfHash, and a second mint of the same block hash reverts. The first confirmed transaction owns it, whichever site it came from. The remaining Bitcoin blocks stay free to look at, with no owner, and a new one arrives every ten minutes.