Revival of the Corpse?

When Professor Eugene saw that the corpse behind the God of War Peter had suddenly sat up from the platform, this scene frightened the old fellow. However, what frightened Professor Eugene was not the revival of the corpse, but the terrifying strength that a creature with a blood oxygen content 100 times that of ordinary people would display once it was revived.

Peter reacted quickly. Before Professor Eugene could finish, he turned to face the revived corpse. Peter knew that calling it a "reactivation" was actually more accurate to use the word "revival."

Needless to say, Betty must have secretly altered this body or triggered a special device in this body while Peter and Professor Eugene were not paying attention, thereby activating the backup energy supply.

It would be easy for Betty to do something within those two hours. However, Peter and Professor Eugene couldn't be blamed for being careless. After all, no one could keep an eye on Betty.