Cheapest priced copy (Commander Legends): $0.35 at Card Kingdom, near mint, their price list as of .
Scrapdiver Serpent 
Creature — Serpent · 5/5 · Common · Scars of Mirrodin · #41
This creature can't be blocked as long as defending player controls an artifact.
Legal inCommanderModernLegacyVintagePauper
Not legal inBrawlStandardPioneer
2 printings · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander Legends | 94 | Common | $0.35 | $0.49 |
| Scars of Mirrodin | 41 | Common | $0.35 | $0.49 |
One ruling from Wizards of the Coast
- 1 January 2011Whether Scrapdiver Serpent can be blocked is relevant only as the declare blockers step begins. If the defending player gains control of an artifact after Scrapdiver Serpent has become blocked, the Serpent will remain blocked.