u/Imaginary-Lie-9496

Small rules question. The other night ghost rider got attacked and took enough damage to be KO'd. When the attack landed he had no power. He took 4 damage, enough to KO him. I wanted to play Deal with the Devil which let's me spend 3 power to return after KO'd

So my question is does he generate that power from the attack before he is KO'd/as he is KO'd or did he not have the power to use that attack.