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Stormtide Leviathan
Creature — Leviathan
Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
All lands are Islands in addition to their other types.
Creatures without flying or islandwalk can't attack.
Rulings (4)
If Stormtide Leviathan loses its abilities, all lands on the battlefield (including those that enter the battlefield later on) will still be Islands in addition to their other types and will still be able to tap to produce blue mana . The way continuous effects work, Stormtide Leviathan's type-changing ability is applied before the effect that removes that ability is applied.
Jul 18, 2014
Islandwalk cares about lands with the land type Island, not necessarily lands named Island.
Jul 18, 2014
Stormtide Leviathan's third ability affects all creatures with neither flying nor islandwalk, regardless of who controls them. They can't attack any player or planeswalker.
Jul 18, 2014
Legality
Formats by platform
Commander
Competitive
Digital
Community & retro
Printings (5)
PIO#75—
Pioneer Masters
CMR#407$2.34
Commander Legends