Defender, flying Prevent all combat damage that would be dealt to and dealt by Fog Bank.
"The union of sea and sky makes a perfect cover." —Talrand, sky summoner
Official Rulings for Fog Bank
7/1/2012 : If Fog Bank blocks a creature with trample, that creature's controller must assign 2 damage to Fog Bank (assuming it's blocking no other creatures, there was no damage marked on it, and nothing has changed its toughness). The remainder can be assigned to the defending player or planeswalker.