Child of the Mists

Prevent all damage that would be dealt to Child
of the Mists.
As Child of the Mists enters the battlefield and at
the beginning of your upkeep, roll a six sided die.
Until your next upkeep, Child of the Mists'
power is equal to the result of the roll.
If a 1 was rolled, prevent all damage that would
be dealt to you and permanents you control until
your next turn.