Echo Protocol

## Echo Protocol 0.5.0-beta.2 — Minecraft 1.21.9–1.21.10

Compatibility port of **Echo Protocol 0.5.0-beta.2 — The House Remembers** to Minecraft 1.21.9 and 1.21.10.

This release does not add new gameplay content. It brings the existing 0.5.0-beta.2 experience to newer Minecraft versions.

### Changes

- Added support for Minecraft 1.21.9 and 1.21.10.
- Updated Yarn mappings and Fabric dependencies.
- Adapted Echo Protocol to Minecraft 1.21.9+ entity and world APIs.
- Updated version-specific rendering and networking compatibility.
- Preserved the modern Echo render-state system.
- Preserved translucent Echo rendering and player skin support.
- Preserved the stable UUID tracked-data implementation.
- Preserved server-authoritative multiplayer privacy.
- Preserved configuration and persistent memory compatibility.
- Verified Memory Echo, Corrupted Echo, Mimic Echo, False Memories, Peripheral Echo, Audio Residue and The Original.
- Verified dedicated-server and real-client startup on both versions.
- The exact same compiled JAR was tested on Minecraft 1.21.9 and 1.21.10.

### Verification

- 50 automated tests: Passed
- Production build: Passed
- Minecraft 1.21.9 server/client: Verified
- Minecraft 1.21.10 server/client: Verified
- Representative gameplay: Verified
- Echo renderer: Verified
- No critical packet, mixin or runtime errors detected

### Requirements

- Minecraft Java Edition 1.21.9 or 1.21.10
- Fabric Loader 0.19.3+
- Fabric API
- Java 21
- Install on both client and server for multiplayer