Last Ninja is a series of video games published by System 3. The first game in the series titled The Last Ninja, was released in 1987 for the Commodore 64 and was one of the most successful games for
1. Compute SHA-256 of OTSCanonicalRecord value → must equal OTSHash 2. Open OTSProofURL → extract Bitcoin block number → must equal OTSBitcoinBlock 3. GET OTSBitcoinBlockVerifyURL → returns the Bitcoin block hash at height OTSBitcoinBlock; GET https://blockstream.info/api/block/{that hash} → its timestamp must match OTSTimestamp 4. Read CopyrightID inside OTSCanonicalRecord → must equal the CopyrightID above 5. GET OTSVerificationAPI → pre-computed 6-check result from server 6. If all match: this entity was registered on CopyrightChains at OTSTimestamp, independently verifiable on Bitcoin Note: an OTS proof may carry multiple Bitcoin attestations; OTSBitcoinBlock is the earliest confirmed one — a later attestation inside the proof corroborates it and is not a mismatch
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8195d90665608b567cfe9d097b8b7f9bc5343d0af4d339e5daefd4890ecd419a. Chain 2 (Bitcoin): anchored in block 954623 (2026-06-20T23:40:06Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/cbec3c0d-6390-4b81-bb44-4853e4031736.json and https://artists.proofprofile.net/proofs/artist/cbec3c0d-6390-4b81-bb44-4853e4031736.ots, the client at https://opentimestamps.org runs `ots verify -f record.json proof.ots`.