If the target land hasn’t been under its controller’s control continuously since the beginning of their most recent turn, that land won’t be able to attack and its {T} abilities won’t be able to be activated. In most cases, that means it will no longer be able to be tapped for mana that turn.
2013-01-24
wotc
Hydroform doesn’t affect the land’s name or any other types, subtypes, or supertypes (such as basic or legendary) the land may have. The land will also keep any abilities it had.
2013-01-24
wotc
Effects that modify power and/or toughness but don’t set them to a specific value (like the one created by Giant Growth), power/toughness changes from counters, and effects that switch a creature’s power and toughness will continue to apply. This may happen if the land was already a creature when Hydroform resolved.
Format Legality
Standard
Not Legal
Future
Not Legal
Historic
Not Legal
Timeless
Not Legal
Gladiator
Not Legal
Pioneer
Legal
Modern
Legal
Legacy
Legal
Pauper
Legal
Vintage
Legal
Penny
Legal
Commander
Legal
Oathbreaker
Legal
Standardbrawl
Not Legal
Brawl
Not Legal
Alchemy
Not Legal
Paupercommander
Legal
Duel
Legal
Oldschool
Not Legal
Premodern
Not Legal
Predh
Not Legal
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