Up for sale is the protective Endoskeleton, an uncommon card from the Urza's Saga expansion of Magic: the Gathering. These are the black-bordered, Korean version.
Endoskeleton: Artifact; you may choose not to untap Endoskeleton during your untap step; spend 2 mana and tap Endoskeleton to have target Creature get +0/+3 as long as Endoskeleton remains tapped; casting cost 2.
These cards are all in at least Very Fine condition, with most being in unplayed, Mint/Near Mint condition.