The Omen of Death
My presence has marked your eventual demise.
Squirrel Girl is a marvel character, and is completely weak and uses squirrel's to fight for the most part as well, so anyone who fights her is fucked.
I probably butchered her joke but that's about what she is in a nutshell (pun totally intended) But yeah I'd say if someone (maybe has just taken the hint to possibly do this) no matter how powerful someone is she could kick their ass here.