Unsettled Mariner 
Creature — Shapeshifter
$3.10 #3965 0.63 7.4 years
Changeling (This card is every creature type.)
Whenever you or a permanent you control becomes the target of a spell or ability an opponent controls, counter that spell or ability unless its controller pays 
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"Whenever you or a permanent you control becomes the target of a spell or ability an opponent controls, counter that spell or ability unless that player pays 4 life."
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Rooftop Percher84%
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Webweaver Changeling83%
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"Changeling"