Cheapest priced copy (Avacyn Restored): $0.35 at Card Kingdom, near mint, their price list as of .
Fervent Cathar 
Creature — Human Knight · 2/1 · Common · Avacyn Restored · #135
Haste
When this creature enters, target creature can't block this turn.
Legal inCommanderModernLegacyVintagePauper
Not legal inBrawlStandardPioneer
2 printings · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Avacyn Restored | 135 | Common | $0.35 | $0.49 |
| Eternal Masters | 129 | Common | $0.35 | $0.49 |
One ruling from Wizards of the Coast
- 8 June 2016The targeted creature can’t block any creatures this turn. The effect doesn’t merely restrict whether it can block Fervent Cathar.