Blood Hustler 

Creature — Vampire Rogue
Whenever you commit a crime, put a +1/+1 counter on this creature. This ability triggers only once each turn. (Targeting opponents, anything they control, and/or cards in their graveyards is a crime.)
{3}{B}: Target opponent loses 1 life and you gain 1 life.
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Cards that do something similar expected a card that isn't here?
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Desiccated Naga 99%
$0.09#27853
"{3}{B}: Target opponent loses 2 life and you gain 2 life. Activate only if you control a Liliana planeswalker."
Vadmir, New Blood 85%
$0.27#8358
"Whenever you commit a crime, put a +1/+1 counter on this card. This ability triggers only once each turn."
Lazav, Familiar Stranger 85%
$0.26#12733
"Whenever you commit a crime, put a +1/+1 counter on this card. Then you may exile a card from a graveyard. If a creature card was exiled this way, you may have this card become a copy of that card until end of turn. This ability triggers only once each turn."
Restless Bloodseeker // Bloodsoaked Reveler 84%
$0.19#11058
"{4}{B}: Each opponent loses 2 life and you gain 2 life."
Shadows of the Past 83%
$0.34#14532
"{4}{B}: Each opponent loses 2 life and you gain 2 life. Activate only if there are four or more creature cards in your graveyard."