Hitbox

Setup

Configure the head bone

Open your .iaentitymodel model file with Blockbench. Create a new bone, it can have any name.

Resize your hitbox.

• XYZ position doesn't matter.

• Only XY size matters, Z does not. This is a Minecraft limitation, it's how hitboxes work in the game.

Rightclick on the bone and select "Bone Config"

Check the "Hitbox" option and press "Confirm".