User blog comment:Zori9/About Charlotte Linlin (Big Mom)/@comment-3425840-20120516083243

I think Big Mom won't be Luffy's ally as that would make Luffy over powered. I also don't think she is an Yonkou. I do think she is the weakest of the Yonkou (like Gecko Moria was the weakest of the Shichibukai). As for her ability, I think it's Mythical Zoan (your theory could as well be correct). Finally I hope Luffy will fight her by the next next arc.