▁Island ▁in ▁a ▁large ▁air ship ▁called ▁the ▁Sul ph ur ▁B ottom ▁to ▁search ▁for ▁the ▁Mother ▁L ode . ▁Bar rel ▁recogn izes ▁a ▁rep orter , ▁Y una , ▁as ▁his ▁lost ▁daughter , ▁Mat ilda ▁C ask ett , ▁who ▁war ns ▁them ▁of ▁the ▁cat ast rop he ▁that ▁could ▁trans p ire ▁if ▁they ▁purs ue ▁their ▁journey . ▁Y una ▁esc apes ▁with ▁her ▁servant , ▁a ▁Re aver bot ▁flying ▁machine - like ▁being ▁named ▁G atz ▁to ▁break ▁the ▁windows ▁for ▁her ▁escape . ▁Ign oring ▁her ▁warning ▁Blue cher ▁continues ▁to ▁the ▁center ▁of ▁the ▁island . ▁Y una ▁orders ▁G atz ▁to ▁give ▁warning ▁sh ots ▁but ▁due ▁to ▁the ▁host ile ▁ret ali ation ▁of ▁the ▁Sul ph ur ▁B ottom , ▁G atz ▁dam ages ▁the ▁engine , ▁forcing ▁the ▁air ship ▁to ▁descend ▁to ▁the ▁island ▁below . ▁ ▁M ega ▁Man ▁Vol n utt ▁and ▁Roll ▁C ask ett ▁watch ▁the ▁events ▁from ▁television ▁and ▁decide ▁to ▁rescue ▁them . ▁With ▁Roll ' s ▁help , ▁M ega ▁Man ▁makes ▁his ▁way ▁to ▁the ▁center ▁of ▁the ▁island ▁and ▁in ▁the ▁process ▁releases ▁a ▁girl ▁called ▁S era ▁and ▁her ▁servant ▁Ge etz , ▁both ▁of ▁whom ▁go ▁to ▁the ▁Sul ph ur ▁B ottom . ▁Ge etz ▁tells ▁Blue cher ▁and ▁Bar rel ▁that ▁the ▁Mother ▁l ode ▁can ▁be ▁accessed ▁by ▁means ▁of ▁four ▁keys . ▁Blue cher ▁and ▁Bar rel ▁ask ▁M ega ▁Man ▁if