Lakithunder is a boss from New Super Mario Bros. for the Nintendo DS. He appears as a castle boss in the secret World 7, meaning that either he or Monty Tank (World 6) must be defeated in order to access World 8. Lakithunder can attack by shooting lightning bolts at Mario, dropping Spinies, or swooping down for a direct hit. That's when the player must jump on him for damage. Three jumps and he gives up his key to Bowser's Underworld.
He also is a boss in Super Mario Galaxy 2. He appears bigger and wears a crown. He is much more aggressive in Super Mario Galaxy 2.