Serene Waterfall

Serene Waterfall enters the battlefield tapped.
{t}: Add {g} or {u}.
{6}{g}{g}, {t}: Until your next turn, skip each
combat step. Activate this ability only during
your first main phase. Serene Waterfall doesn't
untap during your next untap step.
There is something about such scenery that persuades
men to lay down arms.