Cheapest priced copy (Magic 2013): $0.79 at Card Kingdom, near mint, their price list as of .
Ring of Xathrid 
Artifact — Equipment · Uncommon · Magic 2013 · #215
{2}: Regenerate equipped creature. (The next time that creature would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)
At the beginning of your upkeep, put a +1/+1 counter on equipped creature if it's black.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
1 printing · $0.79 to $4.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Magic 2013 | 215 | Uncommon | $0.79 | $4.49 |