Cheapest priced copy (Marvel Super Heroes Commander): $0.79 at Card Kingdom, near mint, their price list as of .
Origin of Black Widow 
Enchantment — Saga · Uncommon · Marvel Super Heroes Commander · #664
(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Each opponent sacrifices a creature of their choice.
II — Creatures you control gain deathtouch until end of turn.
III — Each opponent loses 1 life for each creature card in their graveyard.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
1 printing · $0.79 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Marvel Super Heroes Commander | 664 | Uncommon | $0.79 | $0.79 |