You name the characters yourself and the dialogue is usually whoever is first in line when actually talking. Their are no canon names for the Onion Knights besides the DS remake, though there was a novelization of the game (Japan only of course) back in the day that gave them names, though they are not considered canon. They are: Muuchi, Doug, j. Bowie, and Melfi. Interesting enough, they are three dudes and a girl like the DS version.
Course none of them are going to beat my four man band:
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