Mei, Cryogenics Specialist

Ultimate Charge
If Mei, Cryogenics Specialist would deal combat
damage to a creature, that creature becomes
tapped and can't become untapped until Mei
leaves the battlefield.
{w}{u}: Create a 0/5 Ice Wall token. Activate
only once per turn.
Blizzard—{2}{w}{w}{u}{u},{t}, remove 12 ultimate
counters from Mei: Tap all creatures your
opponents control. Those creatures don't untap
during their controller's next untap step.