Hostile Desert

Oracle Text

T: Add C.

2, Exile a land card from your graveyard: Hostile Desert becomes a 3/4 Elemental creature until end of turn. It's still a land.

Card Rulings

4/18/2017 Desert is a land subtype with no special meaning. It doesn’t grant the land an intrinsic mana ability. Other cards may care about which lands are Deserts.
7/14/2017 If Hostile Desert becomes a creature the same turn it enters the battlefield, you can’t attack with it or tap it for mana.