muffer

blockhead blunderer bonehead botcher bumbler butcher butterfingers clod dolt donkey duffer dunce fool foul-up fumbler goofball idiot ignoramus incompetent klutz numskull spoiler

addlebrain clumsy oaf featherbrain goof-up harebrain mismanager muddler screwup

brain genius

success

bungler clod dolt duffer fumbler klutz lummox schlep

bull in a china shop clumsy oaf clunker foozle