2017-09-29
All attackers are chosen at once. You can't attack with Bishop of Rebirth, return a creature card to the battlefield, and then attack with that creature.
2017-09-29
If the creature returned to the battlefield has any abilities that trigger when creatures attack, those abilities won't trigger.
2017-09-29
If the mana cost of a card in your graveyard includes X, X is considered to be 0.