Harbinger of Night {2}{B}{B}
Creature — Spirit
At the beginning of your upkeep, put a -1/-1 counter on each creature.
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Cards that do something similar expected a card that isn't here?
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Heartmender 98%
$1.04#24274
"At the beginning of your upkeep, remove a -1/-1 counter from each creature you control."
Midnight Banshee 91%
$0.31#4695
"At the beginning of your upkeep, put a -1/-1 counter on each nonblack creature."
Lichenthrope 85%
$0.60#28461
"At the beginning of your upkeep, remove a -1/-1 counter from this creature."
Glistening Oil 80%
$12.56#6769
"At the beginning of your upkeep, put a -1/-1 counter on enchanted creature."