Harbinger of the Seas 
Creature — Merfolk Wizard
$1.60 #3933 1.66 2.3 years
Nonbasic lands are Islands.
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Blood Moon98%
$6.66↑#1553↑2.24↑32.2 years↑
"Nonbasic lands are Mountains."
Magus of the Moon98%
$3.50↑#34301.93↑19.5 years↑
"Nonbasic lands are Mountains."
Zhao, the Moon Slayer85%
$0.28↓#10040↓1.10↓0.9 years↓
"Nonbasic lands enter tapped."
Conversion84%
$0.26↓#26641↓1.16↓33.2 years↑
"All Mountains are Plains."
Glaciers83%
$0.54↓#29298↓1.25↓31.4 years↑
"All Mountains are Plains."
Pale Moon77%
$0.47↓#27922↓0.72↓26.7 years↑
"Until end of turn, if a player taps a nonbasic land for mana, it produces colorless mana instead of any other type."
Illusionary Terrain76%
$0.30↓#25573↓1.18↓31.4 years↑
"Basic lands of the first chosen type are the second chosen type."
Yavimaya, Cradle of Growth76%
$12.10↑#79↑0.41↓5.5 years↑
"Each land is a Forest in addition to its other land types."
Urborg, Tomb of Yawgmoth76%
$51.88↑#75↑0.50↓19.7 years↑
"Each land is a Swamp in addition to its other land types."
Blanket of Night74%
$1.31↓#16830↓0.20↓29.7 years↑
"Each land is a Swamp in addition to its other land types."
Quicksilver Fountain74%
$3.65↑#13681↓0.74↓23.0 years↑
"At the beginning of each player's upkeep, that player puts a flood counter on target non-Island land they control of their choice. That land is an Island for as long as it has a flood counter on it."
Prismatic Omen73%
$3.70↑#34940.24↓18.5 years↑
"Lands you control are every basic land type in addition to their other types."
Blood Sun73%
$0.40↓#15963↓0.86↓8.8 years↑
"All lands lose all abilities except mana abilities."
Alpine Moon73%
$0.30↓#24520↓0.47↓8.3 years↑
"As this enchantment enters, choose a nonbasic land card name."
Back to Basics72%
$2.99↑#5476↓2.16↑28.0 years↑
"Nonbasic lands don't untap during their controllers' untap steps."
Winter Moon72%
$0.60↓#2951↑2.32↑2.3 years
"Players can't untap more than one nonbasic land during their untap steps."
Stormtide Leviathan72%
$0.49↓#2914↑0.93↓16.3 years↑
"All lands are Islands in addition to their other types."
Living Plane72%
$208.78↑#18175↓1.03↓32.4 years↑
"All lands are 1/1 creatures that are still lands."
Nature's Revolt72%
$5.40↑#13255↓0.81↓29.0 years↑
"All lands are 2/2 creatures that are still lands."
Ruination72%
$0.63↓#8454↓2.11↑28.6 years↑
"Destroy all nonbasic lands."