Frosttide Giant

When frosttide Giant enters the battlefield, choose target opponent, at the beginning of chosen opponent's upkeep, draw a card.
Whenever you draw a card, put a frost counter on Frosttide Giant.
At the beginning of your upkeep, if Frosttide Giant has 5 or more counters, all opponents discard their hands, lose 5 life and sacrifice a permanent.