In this datapack, you become Saitama from One Punch Man, having 4 different punching styles each coming with buffs and abilities!

I haven't finished One Punch Man yet (#17 I think), so this is kind of inaccurate, I just imagined what the punches would be like in Minecraft!

The last three slots of your hotbar will be different punching modes, and other hotbar slots will be normal punches, called "Weak Punches".

Sprint while having a punch equipped to run really fast, speed is based on which punch.
Sneak while having a punch equipped to jump really high, jump power is based on which punch.
You are always invincible, even to the void!

What each punch does:

Weak Punch - Normal Minecraft fists
Normal Punch - Instakills almost anything, two punches for a warden, a few punches for the Ender Dragon
Serious Punch, Instakills anything but the Ender Dragon (and wither I think), breaks a lot of blocks where you punched
Very Serious Punch - Creates a massive explosion that destroys blocks and mobs within a ~100 (a guess) block area, even instakills the Ender Dragon when across the entire End island!

When in a world and the datapack is reloaded, type this command to become Saitama:
/tag @s add Saitama

All code by me, obviously inspired by One Punch Man, go read/watch it, it's really good :)