Cheapest priced copy (Dominaria): $0.35 at Card Kingdom, near mint, their price list as of .
Knight of Grace 
Creature — Human Knight · 2/2 · Uncommon · Foundations · #576
First strike (This creature deals combat damage before creatures without first strike.)
Hexproof from black (This creature can't be the target of black spells or abilities your opponents control.)
This creature gets +1/+0 as long as any player controls a black permanent.
Legal inCommanderBrawlStandardPioneerModernLegacyVintage
Not legal inPauper
2 printings · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Dominaria | 23 | Uncommon | $0.35 | $0.49 |
| Foundations | 576 | Uncommon | $0.35 | — |
3 rulings from Wizards of the Coast
- 27 April 2018Knight of Grace only gets +1/+0 if any player controls a black permanent, no matter how many black permanents players control.
- 27 April 2018If an effect says that a creature loses hexproof or can be targeted as though it didn't have hexproof, this applies to hexproof from black as well.
- 27 April 2018"Hexproof from [quality]" is a variant of the hexproof ability. "Hexproof from black" means "This permanent can't be the target of black spells your opponents control or abilities of black sources your opponents control."