Cheapest priced copy (Rivals of Ixalan Promos): $0.49 at Card Kingdom, foil, near mint, their price list as of .
Captain's Hook 
Artifact — Equipment · Rare · Rivals of Ixalan · #177
Equipped creature gets +2/+0, has menace, and is a Pirate in addition to its other creature types.
Whenever this Equipment becomes unattached from a permanent, destroy that permanent.
Equip {1}
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
3 printings · $0.49 to $0.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Rivals of Ixalan Promos | 177 | Rare | — | $0.49 |
| Rivals of Ixalan Promos | 177s | Rare | — | $0.59 |
| Rivals of Ixalan | 177 | Rare | $0.49 | $0.99 |
One ruling from Wizards of the Coast
- 19 January 2018Captain's Hook becomes unattached from the creature it's equipping if you equip it to a new creature, if Captain's Hook leaves the battlefield, if the equipped creature ceases to be a creature, or if Captain's Hook ceases to be an Equipment. (It also becomes unattached if the equipped creature leaves the battlefield, but the triggered ability won't do anything in that case.)