Okami Shiranui

It cannot become night if Okami Shiranui is
on the battlefield.
If Okami Shiranui deals combat damage to a
player, that player must sacrifice a creature they control with the highest power.
This wolf, its coat as brilliant as snow, was dubbed Shiranui. The wolf kept a watchful eye on anyone who ventured outside the village, and made a habit of patrolling the streets at night.