User blog comment:B214/Volume 23 discussion blog/@comment-86.160.39.144-20170520231830/@comment-31137559-20170521005941

It never stated it was discovered. Just that the phone Tiamat had in her hand was connected to a Longinus. I think those other phones involved in Ajuka's gaming industry are of the same type. And when Ajuka asked Issei if he wanted to play his 'game' in Volume 8 and Ajuka said Issei could play through a single mobile phone. It stated that Ajuka knows something about one of the remaining Longinus. Where was it ever stated he found it?