AttributeFix-Sync

Installed next to the original AttributeFix mod, AttributeFix-Sync covers a gap where a server raises or lowers the upper limit of an attribute such as generic.max_health or generic.attack_damage, but connected clients keep the default limit. The server then calculates damage and health against its own cap, while the client still displays values built on the default, which is why tools like Jade, WTHIT and the vanilla health bar can show numbers that do not match the server.

The mod closes that gap through packet synchronization. When a player joins a server that runs it, the server sends the configured maximum values to that client. The client then patches its attribute definitions in memory using a Mixin, so the display follows the real limits. When the player disconnects, the client's original limits are restored, so single-player worlds and other servers are not affected.

AttributeFix-Sync is published for NeoForge only, with a single game version, 1.21.1, and the latest file is 0.0.2 for 1.21.1, dated 2026-02-02. It runs on the client and the server, so both need it. The code is released under the MIT License and is open source.