Ob Nixilis, the Adversary when the casualty cost is paid creates a non legendary token with starting loyalty X. Is the starting loyalty a copiable value so that if you copy the token with say Esika's Chariot it enters with 0 or with 3 loyalty?
Ob Nixilis's casualty ability creates exceptions to the copy effect for casualty (C.R. 707.9). Such exceptions "modify ... characteristic[s] as part of the copying process", and the "final set of values for th[ose] characteristic[s] becomes part of the copiable values of the copy" (C.R. 707.9b). (Also, under C.R. 707.2, "[t]he copiable values are the values derived from the text printed on the object (that text [including] ... supertype ... and/or loyalty)", and under C.R. 109.3, loyalty is a characteristic just as supertype is.)
Ob Nixilis, the Adversary and copying the token