As long as, thig card Remains face-up on the
field; all Demon Warriors your side of the
field are treated as if they are “Fallen” Demon

Once per turn: When an opponent activates the effect of a
Unified card, you can pay (Bloodbourne 4) and discard 1
“Fallen” Demon card from your hand; negate the effect of the
Unified card and destroy it.

You can only control 1 face-up “Fall Of The Fallen”.