Bowser is the final boss of the game, Super Mario Bros. 3.
In the battle, Bowser attacks with fireballs and Ground Pounds. The only way to defeat Bowser is to trick him into Ground Pounding the blocks on the floor until an opening is made. Once the opening is made, the player must evade a final Ground Pound from Bowser to send him flying down the bottomless pit. Princess Peach is then rescued.