{G}{G}{G}{G}{G}: Untap target land you control. It becomes a 5/5 Elemental creature with haste. It's still a land. (This effect lasts as long as that land remains on the battlefield.)
Wakeroot Elemental’s ability can target a land that’s already a creature or a land that’s already untapped. The ability will untap it if possible and set its base power and toughness to 5/5. Any counters or effects modifying that creature’s power and toughness will continue to apply, and any effects that set the creature’s power and toughness will be overwritten.