Infuse SMP Addon
Supported versions of minecraft

This function pack makes it so when you die, you get a negative potion effect, and when you kill someone you get a positive potion effect. This is inspired by a Minecraft Java server, and is done entirely without scripts. This means that it will work through almost any Minecraft update! It also doesn't use any experimental features, so you should be able to put it on a existing world. However, it does use player.json so you will not be able to use it with other addons that use player.json.