If it is not too much to ask, can anyone list all of the promotions and major roles of Bandanna has had that happened before Ultimate's project plan in December 2015. I am currently re-evaluating the chances of him to get an analysis ready for tomorrow.
Kirby Super Star: Was the first opponent in Megaton punch subgame.
Kirby Super Star Ultra: In a newly introduced subgame, Bandana Waddle Dee serves as a King Dedede's right hand man and was even a boss fight. He is the only one that sits in the audience during the Masked Dedede fight.
Kirby Mass Attack: Shares a cameo with Sailor Waddle Dee.
Kirby Return to Dreamland: First time playable, and is the fourth playable character along with King Dedede and Meta Knight. Is a part of the cutscenes so he is a major part of the story.
Kirby Dream Collection: Appears on the title screen along with everyone who was playable in Return to Dreamland.
Kirby Triple Deluxe: Name officially changed to Bandana Waddle Dee. Is in every level as a streetpass feature giving you items.
Kirby and the Rainbow Curse: Kirby and Bandana Waddle Dee are the only major characters to have any role at all in this game. Meta Knight and King dedede only appear as collectibles. Kirby and Bandana Waddle Dee appears in the opening cutscene and they both go on the adventure. While Bandana Waddle Dee isn't required since he is the multiplayer feature of the game, there are a couple of features and events that only happen when he is around. Downside though is for this one game his name was changed to Waddle Dee again.
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I'm going to include Robobot since that was in development during Sakurai's project proposal and most likely had a large majority of the work already completed.
Robobot: Named changed back to Bandana Waddle Dee which it has stayed as ever since. Plays the same role as in Triple Deluxe and had a bunch of unique stickers drawn for this game that you could attach to the robobot armor.
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With all that aside, there is one potential problem. And that is only analyzing Bandana Waddle Dee. Here's the thing. Waddle Dees themselves are insanely popular as well. I don't think they would have ever made a waddle dee into a main playable character if they weren't. A goomba's popularity aren't even comparable to Waddle Dees. Waddle are just as, if not more so, popular than the likes of King Dedede and Meta Knight.
This is a booklet that came with the Kirby Dream Collection game. As you can see straight from the developers mouths, Waddles Dee are one of the most beloved characters in the kirby series.
Not to mention why did they even change Bandana Waddle Dee's name from Waddle Dee. Bandana Waddle Dee was just a fan name for quite a long time. And then suddenly poof, he officially gets called Bandana Waddle Dee. I mean sure, it's a pretty obvious name, but the point was it wasn't something they had to do. And yet they did it anyway.
Now of course, none of these additional things could matter to Sakurai, but I still think they are still pretty special things to think about.
Edit: Also stone cameo in Triple Deluxe and Mii plaza hat.