Fallen Askari

Flanking (Whenever a creature without flanking blocks this creature, the blocking creature gets -1/-1 until end of turn.)
Fallen Askari can't block.

Cadaverous Knight

Flanking (Whenever a creature without flanking blocks this creature, the blocking creature gets -1/-1 until end of turn.)
{1}{B}{B}: Regenerate Cadaverous Knight.

Deathly Ride

Return target creature card from your graveyard to your hand. (Then exile this card. You may cast the creature later from exile.)

Fell Horseman

When Fell Horseman dies, put it on the bottom of its owner's library.

Fell Horseman // Deathly Ride

Locthwain Paladin

Menace (This creature can't be blocked except by two or more creatures.)
Adamant — If at least three black mana was spent to cast this spell, Locthwain Paladin enters with a +1/+1 counter on it.

Curry Favor

You gain X life and each opponent loses X life, where X is the number of Knights you control.