Water Wurm 
Creature — Wurm
$0.23 #31574 0.00 32.2 years
This creature gets +0/+1 as long as an opponent controls an Island.
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"This creature gets +1/+1 as long as an opponent controls an Island."
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"This creature gets +1/+1 as long as an opponent controls an Island."
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"If an opponent controls an Island and you control a Forest, you may cast this spell without paying its mana cost."
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"this card deals damage to each opponent equal to the number of Islands that player controls."
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$0.28↑#6695↑0.11↑26.7 years↓
"If an opponent controls an Island and you control a Mountain, you may cast this spell without paying its mana cost."
Thoughtleech76%
$0.22↓#25083↑0.36↑31.4 years
"Whenever an Island an opponent controls becomes tapped, you may gain 1 life."
Carpet of Flowers75%
$1.75↑#1335↑0.52↑28.0 years↓
"At the beginning of each of your main phases, if you haven't added mana with this ability this turn, you may add X mana of any one color, where X is the number of Islands target opponent controls."
Monsoon74%
$0.95↑#274210.62↑31.4 years
"At the beginning of each player's end step, tap all untapped Islands that player controls and this enchantment deals X damage to the player, where X is the number of Islands tapped this way."
Seasinger73%
$0.27↑#21396↑0.44↑32.0 years
"When you control no Islands, sacrifice this creature."
Scald73%
$0.29↑#257311.12↑28.0 years↓
"Whenever a player taps an Island for mana, this enchantment deals 1 damage to that player."
Choke72%
$0.86↑#17577↑1.76↑29.0 years↓
"Islands don't untap during their controllers' untap steps."
Curse of Marit Lage70%
$2.66↑#258381.32↑31.4 years
"Islands don't untap during their controllers' untap steps."
Marshdrinker Giant70%
$0.11↓#305240.50↑18.2 years↓
"When this creature enters, destroy target Island or Swamp an opponent controls."