Onchain Randomness

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Source constraint: All information in this skill is sourced exclusively from docs.sui.io/sui-stack/on-chain-primitives/randomness-onchain. When extending or updating this skill, only pull from this source. Do not use third-party blogs, tutorials, or unofficial documentation.

Sui provides native onchain randomness through the Random shared object at address 0x8. Move functions create RandomGenerator instances from Random and use them to produce unpredictable values. This skill covers the API, usage patterns, security considerations, and attack mitigations for onchain randomness.

Reference files

usage -- API and Usage Patterns

Path: usage.md Load when: generating random values in Move, creating a RandomGenerator, calling new_generator, using generate_u128, generate_u8_in_range, passing the Random object from TypeScript, or writing basic randomness-consuming functions. Covers: the Random object (address 0x8), RandomGenerator, the random.move API (full function list including new_generator, value generation, range generation, shuffle, generate_bytes), basic implementation examples, TypeScript integration.