Deathbringer Regent 


Creature — Dragon
Flying
When this creature enters, if you cast it from your hand and there are five or more other creatures on the battlefield, destroy all other creatures.
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Cards that do something similar expected a card that isn't here?
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Wakening Sun's Avatar 86%
$0.36#3158
"When this creature enters, if you cast it from your hand, destroy all non-Dinosaur creatures."
Death-Rattle Oni 85%
$0.16#17187
"When this creature enters, destroy all other creatures that were dealt damage this turn."
Spreading Plague 82%
$12.06#15451
"Whenever a creature enters, destroy all other creatures that share a color with it. They can't be regenerated."
Reiver Demon 81%
$0.76#10391
"When this creature enters, if you cast it from your hand, destroy all nonartifact, nonblack creatures. They can't be regenerated."