Cheapest priced copy (Iconic Masters): $0.35 at Card Kingdom, near mint, their price list as of .
Doorkeeper 
Creature — Homunculus · 0/4 · Common · Return to Ravnica · #37
Defender
{2}{U}, {T}: Target player mills X cards, where X is the number of creatures you control with defender.
Legal inCommanderPioneerModernLegacyVintagePauper
Not legal inBrawlStandard
3 printings · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Iconic Masters | 53 | Common | $0.35 | $0.49 |
| The List | IMA-53 | Common | $0.35 | — |
| Return to Ravnica | 37 | Common | $0.35 | $0.49 |
One ruling from Wizards of the Coast
- 1 October 2012The number of creatures with defender you control is counted when the ability resolves.