Ozo, the Indolent

Ozo, the Indolent enters the battlefield tapped and doesn't untap during your untap step.
{b}{b}{g}{g}, Discard a card: Untap Ozo.
{t}: Tap all lands target player controls. Nonbasic lands controlled by that player don't untap during their next untap step. Activate this ability only any time you could cast a sorcery.