It's revealed that the atomic bomb that destroyed Brooklyn, was a special dimensional bomb, sending the Ex-Mutants and Dr Cugat to different dimensions.
ɪts ɹᵻvˈiːld ðætðɪ ɐtˈɑːmɪk bˈɑːm ðæt dᵻstɹˈɔɪd bɹˈʊklɪn, wʌzɐ spˈɛʃəl dᵻmˈɛnʃənəl bˈɑːm, sˈɛndɪŋ ðɪ ˈɛksmjˈuːtənts ænd dˈɑːktɚ kjˈuːɡæt tə dˈɪfɹənt dᵻmˈɛnʃənz.