Contagion 
Instant
$0.29 #12665 0.17 30.2 years
You may pay 1 life and exile a black card from your hand rather than pay this spell's mana cost.
Distribute two -2/-1 counters among one or two target creatures.
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Sickening Shoal82%
$10.05↑#19381↓0.47↑21.6 years↓
"You may exile a black card with mana value X from your hand rather than pay this spell's mana cost."
+1 more matching line
Splendid Agony82%
$0.14↓#150590.00↓9.4 years↓
"Distribute two -1/-1 counters among one or two target creatures."
Force of Despair78%
$7.69↑#2425↑0.57↑7.2 years↓
"If it's not your turn, you may exile a black card from your hand rather than pay this spell's mana cost."
Unmask78%
$6.28↑#18001↓0.45↑26.9 years↓
"You may exile a black card from your hand rather than pay this spell's mana cost."
Sick and Tired78%
$0.10↓#31039↓0.00↓27.6 years↓
"Two target creatures each get -1/-1 until end of turn."
Soul Spike78%
$16.96↑#26001↓0.50↑20.1 years↓
"You may exile two black cards from your hand rather than pay this spell's mana cost."
Demon of Death's Gate77%
$2.39↑#135930.1416.1 years↓
"You may pay 6 life and sacrifice three black creatures rather than pay this spell's mana cost."
Grind // Dust75%
$0.14↓#26473↓0.47↑9.1 years↓
"Put a -1/-1 counter on each of up to two target creatures."
Ruthless Disposal74%
$0.14↓#25381↓0.00↓10.1 years↓
"Two target creatures each get -13/-13 until end of turn."
Incremental Blight73%
$0.22↓#6231↑0.00↓18.3 years↓
"Put a -1/-1 counter on target creature, two -1/-1 counters on another target creature, and three -1/-1 counters on a third target creature."
Force of Will72%
$58.18↑#192↑2.01↑30.2 years
"You may pay 1 life and exile a blue card from your hand rather than pay this spell's mana cost."
Pyrokinesis72%
$1.45↑#5331↑0.61↑30.2 years
"You may exile a red card from your hand rather than pay this spell's mana cost."
+1 more matching line
Greater Werewolf72%
$0.17↓#30470↓0.1930.9 years
"At end of combat, put a -0/-2 counter on each creature blocking or blocked by this creature."
Nefashu71%
$0.30↑#20718↓0.30↑23.3 years↓
"Whenever this creature attacks, up to five target creatures each get -1/-1 until end of turn."
March of Wretched Sorrow70%
$0.36↑#9319↑0.39↑4.5 years↓
"As an additional cost to cast this spell, you may exile any number of black cards from your hand. This spell costs 
less to cast for each card exiled this way."
less to cast for each card exiled this way."
Retribution70%
$0.17↓#28426↓0.30↑30.9 years
"Choose two target creatures controlled by the same opponent. That player chooses and sacrifices one of those creatures. Put a -1/-1 counter on the other."
Grief70%
$3.10↑#6454↑1.01↑5.3 years↓
"Evoke—Exile a black card from your hand."