aitatata! and twunderu refer to the same artist, except that twunderu doesn't have a valid artist entry, so the Find artist mechanism doesn't pick it up. Thus the tags should be aliased one way or another. Personally I find aitatata! nicer, plus it's the artist's chosen handle. It seems stable, it hasn't changed in any way for the past few months at least, so I think we can assume it's what he really goes by.
Updated by jxh2154