Cheapest priced copy (Archenemy): $0.35 at Card Kingdom, near mint, their price list as of .
Synod Sanctum 
Artifact · Uncommon · Mirrodin · #252
{2}, {T}: Exile target permanent you control.
{2}, Sacrifice this artifact: Return all cards exiled with this artifact to the battlefield under your control.
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper