Bryce, the Ice King

Menace
Trample
Whenever Bryce, the Ice King attacks, any creature
that takes damage from his attack are tapped and
don't untap during your opponent's next untap step.
You may exert Bryce, the Ice King as he attacks. If
you do, he gains +6/+0 until end of turn, and he
deals 4 damage to up to 3 other targets.