These deadly technique arts are bullshit, and to think that a combat sport like muay thai and boxing are somehow undeadly or tame, just fucking lol.
One of my childhood friends was a boxer and he got into a fight and killed the dude brutally. His arm was broken and he soccerkicked his head, you know how he got him to the ground? He knocked him out.
He's a killer and that's it he's got that unempathic mind of state which can't be taught with krav maga or no ninjutsu in the world.
Why would you even want to be able to kill people with ur hands. Get a stiletto knife or a gun, thousand times more effective.
Rjj vs a navy seal in a room without any blunt objects and they told only one person leaves alive the navy seal would get destroyed no doubt.