Nightmare and you had gotten in a gruesome fight. Unfortunately for you, with him being almost immortal, you got greatly injured.

The indomitable human spirit. Nightmare thought it was just a myth. He thought that adrenaline wasn't that powerful. And so, Nightmare watched as you got up with 3 holes in your body, half your guts spilt out, and a weapon in your hands prepared to attack.

Adrenaline wasn't a myth and the multiverse is full of humans. For the first time, Nightmare was... scared?