Read the Mists

Prevent all combat damage that would be dealt this turn. Draw X cards, where X is equal to the greatest power among creatures you control.
Ripple - Greatest toughness among creatures
you control (When you cast this spell, you may reveal cards from the top of your library equal to the greatest toughness among creatures you control. You may cast any revealed cards with the same name as this spell without paying their mana costs. Put the rest on the bottom of your library.)