The new 1.21.9 Pre-Release 2 looks like a tidy list of tweaks, but it quietly recalibrates how contraptions, datapacks, and creative pipelines behave together. This release tightens AI timing for copper golems, removes obscure edge cases around world spawn logic, and smooths performance pitfalls that disproportionately affect servers and creators who iterate fast.
What changed
Pre-Release 2 concentrates on copper golem behavior parity, datapack version alignment, and a batch of bug fixes that clean up regressions from earlier snapshots. The highlights: copper golems oxidize even when the day-night cycle is frozen, the statue transition is faster and less picky about exact positioning, and the Data Pack version is bumped to 88.0 to match recent command behavior changes.
Copper golem, re-tuned
The copper golem now oxidizes regardless of the doDaylightCycle rule, restoring predictable progression in creative testing worlds, lobbies, and servers with locked time. The statue conversion no longer requires being perfectly centered in an empty block, reducing odd “stuck” moments in showcases and farms. When fully oxidized, a golem can become a statue immediately, improving timing determinism for redstone builds that depend on that transition.
- Oxidizes with time frozen, eliminating a counterintuitive blocker for mapmaking and server hubs.
- Drops the center-of-block requirement, cutting friction in build displays and automation.
- Enables immediate statue at full oxidation, reducing latency and weird AI stalls.
Performance and stability ripple effects
This pre-release addresses an occasional sound crash during resource pack reloads and a copper golem chest-check lag spike—two issues that punish creators and servers that iterate and stress test. It also includes mannequin and text display fixes that remove visual and collision inconsistencies that can derail presentation-grade builds.
- Resource pack reload sound crash fixed, shortening creator iteration loops.
- Copper golem chest-check lag spike reduced, easing heavy-entity test scenarios.
- Mannequin hitboxes and text display billboarding corrected for consistent visuals and interactions.
Datapack ecosystem: version 88.0
The datapack version moves to 88.0, explicitly aligning with recent changes to world spawn commands such as /setworldspawn and /spawnpoint. This avoids silent breakages and signals authors to update schemas and test logic before the wider release. It’s the plumbing that keeps adventure maps, spawn systems, and lobbies behaving after upgrades.
- Datapack compatibility at 88.0 to match command behavior changes.
- Clear prompt for authors to migrate spawn logic and test dimension-specific cases.
Cross-dimension correctness
A subtle fix addresses how dimension-specific world spawn points could interfere with mob spawning elsewhere. That kind of cross-dimension bug knocks challenge maps, multi-dimension SMPs, and curated spawn logic off balance. Restoring isolation between spawn settings and mob behavior keeps farms and survival pacing intact.
- Dimension-specific world spawn no longer disturbs mob spawning in other dimensions.
- Farm yields and survival balance return to expected baselines.
Quality-of-life and parity touches
Smaller fixes matter to creators aiming for polish. Nameplate positioning for specific usernames, mannequin hitbox precision in posed states, and corrected text display billboarding all reduce the rough edges that show up in museums, galleries, and minigame UIs.
- Corrected below_name plate height for special cases like “deadmau5.”
- Reliable mannequin collisions for posed states.
- Predictable text display facing for signage and overlays.
Impact on servers and creators
- Snapshot readiness: With crash and lag fixes, it’s safer to test builds and packs, though backups and isolated test worlds remain essential.
- Redstone predictability: Copper golem timing and positioning changes remove “ghost” delays and stuck states that used to break contraptions.
- Content pipeline: Resource pack reload stability helps texture and sound authors, while the datapack bump gives a clear migration target before the final release.
Practical upgrade guidance
- Enable snapshots in the launcher’s Installations tab and test in separate worlds to protect long-term saves.
- For datapacks, bump to 88.0 and re-test /setworldspawn and /spawnpoint across all used dimensions.
- If using copper golem logic near storage systems, retest chest-interaction density and entity counts to validate the lag improvements.
Key bug fixes at a glance
- Copper golems oxidize even when time is frozen.
- Resource pack reload sound crash resolved.
- Server management protocol improvements for by-name parameters.
- Corrected below_name plate height for “deadmau5.”
- Reduced copper golem chest-check lag spikes.
- Faster statue transition at full oxidation.
- Fixed mannequin hitboxes when posed.
- Restored correct text display billboarding.
- Dimension-specific world spawn no longer breaks mob spawning elsewhere.
- Documented command behavior that requires datapack minor-version updates.
Last Updated on September 22, 2025 by Lucy
