Cheapest priced copy (Magic 2012): $2.99 at Card Kingdom, near mint, their price list as of .
Worldslayer 
Artifact — Equipment · Rare · Mirrodin · #276
Whenever equipped creature deals combat damage to a player, destroy all permanents other than this Equipment.
Equip {5} ({5}: Attach to target creature you control. Equip only as a sorcery.)
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
2 printings · $2.99 to $19.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Magic 2012 | 222 | Rare | $2.99 | $16.99 |
| Mirrodin | 276 | Rare | $3.99 | $19.99 |
One ruling from Wizards of the Coast
- 22 September 2011The equipped creature is also destroyed.