Dedede is often selfish and greedy, but ultimately has the good of himself and his subjects at heart. In battles, rather than using his natural abilities he prefers making use of his weapon of choice and most prized possession, a large wooden hammer.
Dedede and Mezzo have a long-standing rivalry, mainly due to their shared love of sweets.
Dedede has a small army of Jigglypuff loyal to him. It is unknown how he originally gained their trust. One of the more notable members is one that wears a blue bandanna.
Dedede is the self-proclaimed king of the Dream World, though the only Pokémon that recognize his rule are his Jigglypuff army. He first crossed paths with Mezzo after she foiled an attempt from him to steal all of the sweets in the Dream World.
Still later, he crossed into the waking world through a Dream Rift and attempted to establish a power base there. Mezzo returned him to the Dream World as the rifts were closed.