(Activate),Remove from the game any number of cards from the top of your deck-->Exhaust target character unless it's controller removes more cards from the top of his deck.

I'm trying to figure out how to best make use of this new Doom..here's a question that comes to mind: what happens if I remove my whole deck? Does my KO pile go into my deck at that point? If so,can those cards be removed as well?
Thanks in advance for any help!

Why would your KO'd pile move?

Of course not. When you run out of deck, your deck is simply gone. It does not replenish itself from any source unless specified by an effect like Lockup or MUN Human Torch.

u just dont have a deck

What would be interesting to do is use him in a IG handflood type deck, and maybe a little bit of the other MUL characters and use Doom to exhaust a guy or deck you opponent.

I.E. they have 20 cards left in their deck and you use Doom to exhaust their hiest drop or lets say remove 8-10 cards from the game.

Thanks for your help men. I've never encountered an "empty deck" before in VS, and I've played some other ccg's that let your discard pile replenish the deck. So your explanations clear that up a lot for me-
thanks again