A large, blunt rock, happily provides knockback resistance.
Note: Minify the command to avoid issues :)
One Hit Kill Stick
Kill sign
Knife
Rock
go 1000mph with a walking stick
TnT
Get cool minecraft banners in ONE COMMAND NO MODS!
Herobrine's Flesh
mysticspyralman
mysticspyralman
lunaglimmer
dantdm
orangecreep3r
cyarith