So say I attack with a {Vampire Nighthawk} equipped with a {Trepenation blade} but they cast a spell like {Rebuke} would he die before they discard cards from library or after?
Before. The Trepanation Blade would go on the stack, followed by Rebuke. Rebuke resolves and kills him, then your trigger resvolves.
Awe sad day :/
But they'd still mill, right?
Since the trep blade trigger was on the stack?
I believe it would as the text just says when equipped creature attacks, not when it does combat damage. The creature attacked, that can't change.
Yes the trigger would still happen, not sure who I am quoting but. "Once the archer has shot the arrow, you can kill the archer but you will still get hit by the arrow"
So they'd mill but take no damage? Still cool lol