I humbly offer up the next two R.E.B.E.L.S. covers for your perusal and (one hopes) enjoyment. These would be for #17 and #18, respectively, one featuring hawks and one featuring brain(iac)s.
I guess the argument could be made that every issue of R.E.B.E.L.S. features Brainiacs, but this one features 3 (count 'em 3!) generations of 'em.