Mjolnir Datapack

This datapack adds Thor’s hammer, or more precisely, Mjölnir. As soon as you hold this hammer in your hand, you will receive an infinite Speed II effect. If you hit a mob/player with this hammer, the target will receive Blindness and Slowness for 2 seconds, and lightning will strike them.

To make the datapack work, place it in your world’s datapacks folder:

minecraft/saves/"Your World"/datapacks

Then type this command once in chat:

/reload

After reloading, a command will appear in the chat that you can use to obtain the hammer:

/function mjolnir:give