Cheapest priced copy (Shadows over Innistrad): $0.35 at Card Kingdom, near mint, their price list as of .
Ravenous Bloodseeker 
Creature — Vampire Berserker · 1/3 · Uncommon · Shadows over Innistrad · #175
Discard a card: This creature gets +2/-2 until end of turn.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
2 printings · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Shadows over Innistrad Promos | 175 | Uncommon | — | $0.49 |
| Shadows over Innistrad | 175 | Uncommon | $0.35 | $0.49 |
One ruling from Wizards of the Coast
- 8 April 2016You can activate Ravenous Bloodseeker's ability any number of times to discard several cards. It will be put into its owner's graveyard once its toughness is 0 or less. Any other instances of the ability still on the stack will resolve with no effect.