the maester had taught him all the banners : the mailed fist of the glovers , silver on scarlet ; lady mormont 's black bear ; the hideous flayed man that went before roose bolton of the dreadfort ; a bull moose for the hornwoods ; a battle-axe for the cerwyns ; three sentinel trees for the tallharts ; and the fearsome sigil of house umber , a roaring giant in shattered chains .