Rawa, the Living Marsh

Swampwalk
Landfall - Whenever a land enters the battlefield
under your control, choose one: tap or untap
target permanent; target creature you control
gets +2/+2 and gains trample until end of turn;
or target creature you control gains deathtouch
until end of turn.
{3}{g}: Target land becomes a 3/3 green and black
Elemental creature. It's still a land.