land ers ▁novel ▁series ▁by ▁Mark ▁Ell is , ▁the ▁An unn aki ▁are ▁revealed ▁to ▁have ▁been ▁the ▁cul pr its ▁behind ▁a ▁dev ast ating ▁nuclear ▁war ▁as ▁well ▁as ▁the ▁Root ▁Race ▁of ▁the ▁so - called ▁Gray ▁al iens . ▁ ▁The ▁Marvel ▁com ic ▁series ▁The ▁E tern als ▁de als ▁with ▁advanced ▁al iens ▁( the ▁Cel est ial s ) ▁who ▁had ▁experiment ed ▁on ▁early ▁hom in ids , ▁creating ▁two ▁sister ▁races , ▁the ▁E tern als ▁and ▁the ▁De vi ants , ▁who ▁res emble d ▁" god s " ▁and ▁" dem ons " ▁respectively . ▁It ▁is ▁also ▁noted ▁that ▁their ▁advanced ▁test ▁eventually ▁lead ▁to ▁the ▁X - g ene ▁in ▁mut ants . ▁ ▁Y osh iki ▁Tak aya ' s ▁m anga ▁series ▁Bio ▁Bo oster ▁Arm or ▁Guy ver , ▁later ▁adapted ▁several ▁times ▁into ▁animated ▁form ▁and ▁twice ▁into ▁a ▁pair ▁of ▁amer ican ized ▁films , ▁featured ▁the ▁idea ▁that ▁all ▁life ▁on ▁earth ▁was ▁created ▁by ▁an ▁organization ▁of ▁various ▁al ien ▁be ings ▁as ▁bi ological ▁weapons ▁intended ▁for ▁use ▁in ▁inter stell ar ▁war , ▁which ▁were ▁later ▁abandoned ▁for ▁reasons ▁unknown , ▁and ▁thus ▁were ▁never ▁taken ▁into ▁space . ▁According ▁to ▁the ▁series , ▁human ▁be ings ▁are ▁actually ▁a ▁' first ▁stage ' ▁organ ism ▁that ▁can ▁be ▁further ▁mut ated ▁into ▁mon str ous ▁cre atures ▁called ▁Zo ano ids , ▁which ▁supposed ly ▁account ▁for ▁many ▁modern