Cheapest priced copy (Rivals of Ixalan): $0.49 at Card Kingdom, near mint, their price list as of .
Bishop of Binding 
Creature — Vampire Cleric · 1/1 · Rare · Rivals of Ixalan · #2
When this creature enters, exile target creature an opponent controls until this creature leaves the battlefield.
Whenever this creature attacks, target Vampire gets +X/+X until end of turn, where X is the power of the exiled card.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
2 printings · $0.49 to $0.79 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Rivals of Ixalan Promos | 2s | Rare | — | $0.79Out of stock |
| Rivals of Ixalan | 2 | Rare | $0.49 | $0.79 |
6 rulings from Wizards of the Coast
- 19 January 2018If there is no exiled card as Bishop of Binding’s last ability resolves, most likely because Bishop of Binding left the battlefield while that ability was on the stack, X is 0. The same is true if the exiled card doesn’t have a power, most likely because it’s a noncreature card that had become a creature.
- 19 January 2018Auras attached to the exiled creature will be put into their owners’ graveyards. Any Equipment will become unattached and remain on the battlefield. Any counters on the exiled creature will cease to exist.
- 19 January 2018If a Vehicle is exiled with Bishop of Binding, use its printed power to determine the value of X.
- 19 January 2018If a token is exiled this way, it will cease to exist and won’t return to the battlefield.
- 19 January 2018If Bishop of Binding leaves the battlefield before its first triggered ability tries to resolve, the target creature won’t be exiled.
- 19 January 2018The value of X is determined only as Bishop of Binding’s second ability resolves. It won’t change if the card leaves exile later in the turn.