Critical Knock-Out

When you get KO'd by an attack that you should've survived, had it not landed a critical hit.
CKO for short.

Game: Enemy attacks!
Player: No worries, I can survive this.
Game: Critical hit!
You've been defeated...
Player: Ugh! I hate Critical Knock-Outs!

Knock-It-Out-Of-The-Park-Er

A person who succeeds at everything they do.

Me: I love Paul Allen! That guy right there is a real knock-it-out-of-the-park-er!
You: Yeah, I hate him.

Knocking out a skeleton

When you have been locked down for so long you have literally turned your dick into a skeleton, have no feeling left, and cannot complete the task, due to the lack of sex from too much wanking

I wish this Lockdown would finish

Why is that?

I've started knocking out a skeleton

Dude that's bad, you can't even try the stranger in that situation!