Cheapest priced copy (Shadows over Innistrad): $0.99 at Card Kingdom, near mint, their price list as of .
Goldnight Castigator 
Creature — Angel · 4/9 · Mythic · Shadows over Innistrad · #162
Flying, haste
If a source would deal damage to you, it deals double that damage to you instead.
If a source would deal damage to this creature, it deals double that damage to this creature instead.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
2 printings · $0.99 to $2.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Shadows over Innistrad Promos | 162s | Mythic | — | $2.49 |
| Shadows over Innistrad | 162 | Mythic | $0.99 | $1.49 |
2 rulings from Wizards of the Coast
- 8 April 2016If you control two Goldnight Castigators and a source would deal damage to you, it deals four times that much damage instead. If you control a third Goldnight Castigator, the source deals eight times that much damage to you, and so on. Damage dealt to a Goldnight Castigator is only doubled, regardless of how many are on the battlefield.
- 8 April 2016If multiple replacement effects could apply to damage being dealt to you or Goldnight Castigator, you choose the order to apply those effects.