Strain 556 is the 556th adapted genome of genestealer as modified by Magos Hermiatus, whether this was done by the original Hermiatus or his subsequent brood clones none can tell, scientific records in secundus post destruction are sketchy at best...

Hervaann was once a mere mook of the patriarch, then the brood clone continued his experiments l, with more genetic material forcibly integrated the mutations ran amok