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Blightcaster
{3}{B}
Creature -- Human Wizard
2/3
Whenever you cast an enchantment spell, you may have target creature get -2/-2 until end of turn.

Death Pulse
{2}{B}{B}
Instant
Target creature gets -4/-4 until end of turn.
Cycling {1}{B}{B} ({1}{B}{B}, Discard ~this~: Draw a card.)
When you cycle ~this~, you may have target creature get -1/-1 until end of turn.

Dreamspoiler Witches
{3}{B}
Creature -- Faerie Wizard
2/2
Flying
Whenever you cast a spell during an opponent's turn, you may have target creature get -1/-1 until end of turn.

Fourth Bridge Prowler
{B}
Creature -- Human Rogue
1/1
When ~this~ enters, you may have target creature get -1/-1 until end of turn.

Undead Executioner
{3}{B}
Creature -- Zombie
2/2
When ~this~ dies, you may have target creature get -2/-2 until end of turn.