He was a former rival of Donkey Kong from 1994 until 2008. Since then, he hasn't appeared in any Nintendo Games (Including any Donkey Kong Games) at all. Sure, he was seen as a couple cameos, but the fans wish they can see this overweight, royal yet malicious Kremling back in action. He's a good choice for a comeback according to the Nintendo Community and he has yet to return somehow...
He was never included in the Super Mario Mash-Up Pack, but this is a close concept of what he would look like if he was featured. I used various assets of Bowser and Kamek with a couple retouches to make this concept. Feel free to add him back to the Mushroom Kingdom if you desire! (For W4HdaB3ST and his Super Mario Mash-Up Pack PC Port Project)