Cheapest priced copy (Tempest): $1.99 at Card Kingdom, near mint, their price list as of .
Reap 
Instant · Uncommon · Tempest · #247
Return up to X target cards from your graveyard to your hand, where X is the number of black permanents target opponent controls as you cast this spell.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
2 printings · $1.99 at Card Kingdom
2 rulings from Wizards of the Coast
- 1 April 2008The count of the number of black permanents the targeted opponent controls is done during announcement since it only affects target selection. It does not get recounted later.
- 1 April 2008This card has received errata so that it now targets a specific opponent.