Half-Heart Hardcore

Version 1.0.0 is the only version legal for speedrunning.

This mod transforms all game worlds into hardcore mode and limits the player's maximum health to just half a heart. In Minecraft versions 1.3 to 1.12.2, the mod fixes heart rendering on the client side. Except for this feature, for all versions it operates on the logical server - meaning compatibility with multiplayer worlds when installed on the server, and with singleplayer games or local networks where you act as host when installed on the client.

For versions 1.3-1.12.2, the mod uses Legacy Fabric. Installation on both client and server is recommended, but technically having it on the logical server is sufficient. In version 1.13 and above, installation only on the server is enough.

For early versions 1.0-1.2, the mod loads through Ornithe and works exclusively on the client side. When used on a server, all players will be limited to half a heart, but hardcore mode won't activate since multiplayer hardcore was added later in the famous 12w18a snapshot.

The mod should work with most development snapshots, though complete testing isn't possible. It's known to be compatible with the infinity snapshot (20w14infinite, related to dimensions).