Dark Dark Kirby

Dark Dark Kirby is a gag character fusion in the Kirby's Cornfuffs Saga, only appearing in Part 1 of Meta Knight Story. He is the combination of Dark Kirby and Dark Matter and a parody of the fact characters were constantly getting possessed and fusing to become more powerful (and get Dark before their name). This is made all the more ridiculous by the fact that Dark Kirby had already absorbed 300/301ths of Dark Matter's power, but was only able to transform into Dark Dark Kirby by absorbing the remaining 1/301th.

Dark Dark Kirby is destroyed almost as quickly as he's created, demanding as soon as the fusion is formed that Gooey let go of his hand... not realizing Gooey had grabbed his hand because he'd slid off the ship during his transformation. Gooey obliges, and Dark Dark Kirby falls off the Dyna-Halberd, splitting back into Dark Kirby and Dark Matter from the g-force as they plummet. This fusion is never seen again.