- ItemManager(uint seed, ...) refuses seed 0 and seeds Random from it.
- RunStart.ItemSeed(galaxy, step) is public (formula unchanged), refuses a
zero result; named steps ArenaStep, StageStep, ContinueStep and NoRunSeed.
- Continue seeds the item stream from the saved run's seed (ContinueStep);
a scene with no galaxy uses NoRunSeed.
- Zone's unpack scatter draws SimulationDice.For(CombatSeed, ScatterStream,
1-based pack ordinal), never the item stream.
- Loadout's scratch manager and AetherDb's catalog command take fixed seeds;
every test and Editor construction gains 1u (mechanical rewrite).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>