SPOILERS BEYOND SPOILERS.
We have done it.
Through weeks and weeks of thought, theorizing, replaying, and daydreaming
The ENTIRE Canon of Kirby: Planet Robobot.
First off, let me just say, with my previous theories, I was a little pushy about making you believe it. I apologize. Sorry.
So first, we have the story mode. This is as what it is confirmed to be in the Ask-A-Thons. You can see there cuz i'm too lazy to post them here.
Then we have Meta Knightmare Returns. So Star Dream has reality-bending powers, right? So, I think ,as it was being drilled into, it created a new, stronger dimension WITHOUT KIRBY. But he did not think of Meta Knight. So, after rescuing Kirby from being smushed, he went off to the other world, before the portal closed. But he did not do a head-on assult, like last time. He followed Kirby's strategy. But he did not want the portal to close without him, so he made it a little time-attack. When Star Dream was encountered, he was still a machine. So he thought as Meta Knight as the new admin and sent all the enemies at him.
Then we have The Arena. I think this is a simulation made for training for later encounters. As we saw in previous games and the anime, Meta Knight is kind of power-hungry and also likes to train our pink hero. So he made a boss rush! But he also likes a fair fight, so he let Kirby have any weapon he chooses!
Then, the True Arena. Everything goes as planned, harder arena. But Star Dream's soul still wanders. And he finds the simulation, and infects it. He then uses his powers to make it a reality. So Kirby fights him, he fuses, a Haltmann-Designed Nova is underneath, and Kirby uses his drill. But Star Dream is one step ahead. He inhales Kirby. But by destroying the heart, he destroys the soul, and Star Dream is gone forever.
But what about Kirby 3D Rumble and Team Kirby Clash? Simple. For 3D Rumble, Masher is on the attack! Kirby must go to a new land to save it! And Kirby Clash? Well first, I think that the yellow, green, and red Kirbies are the Kirbies that were formed when Dark Meta Knight split Kirby up in a failed attempt to kill him. Now, we all like role-playing, let's not deny it. And TKC is no different. The Kirbies pretend to be medieval heroes, running around defeating bosses!
So that's my theory. Thank you.
(Credits roll as dramatic music plays)
And I'll see y'all next time!