Since it's a Kirby - centered fanfiction, Kirby is most likely one of the main characters. There could also be other characters from the Kirby games that Kirby might be fighting against or teaming up with in this death battle scenario.
Well, Kirby would definitely be a main character. In addition, depending on the plot of the fanfiction, there might be some of Kirby's classic enemies like King Dedede or Meta Knight. King Dedede could be in the story as an antagonist in the death battles, trying to defeat Kirby for his own reasons. Meta Knight, on the other hand, could be either an ally or an opponent, depending on how the author wants to write the story. There might also be some original characters created by the fanfiction author to add more variety to the battles.
The main character would be Kirby without a doubt. However, other potential main characters could be characters from other universes if this is a crossover type of death battle fanfiction. For example, if it's a crossover with the Sonic the Hedgehog universe, Sonic could be another main character and they could be in a death battle against each other or teaming up against a common enemy. Or perhaps characters from other Nintendo franchises could be involved too, like Mario or Link, and their presence would change the dynamics of the death battles in the fanfiction.
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