This datapack is a fully autonomous mechanic change where every single time you kill a mob, passive or hostile, you get a random Minecraft effect. Most are permanent and cannot be cured with a milk bucket. There are a few exceptions like levitation, instant health, bad omen, etc. Super easy to use, just drag and drop the file into a Minecraft world when creating it.
Two separate versions, one for 1.16.5 and one for 1.18.2.