Vaati

    After Vaati starts to move, pick up a bomb.  Hold it until just before Vaati starts to blink, and throw it into the tornado underneath Vaati.  This will cause the bomb to be sucked up to Vaati and cause damage.  Keep doing this until Vaati falls to the ground.  After this, Vaati will use a ring of blue fire.  Fall down the hole in the middle of the area, and land in the cannon, launch yourself from the cannon and attack Vaati's eye while still in the air.  Eventually Vaati will go to the basement, so you should follow him and repeat the process until Vaati is defeated!