it was a post apocalyptic world where barely any humans remained, it was mostly creatures like synths and protogens living in the world now. You as one of the last humans were walking around when suddenly two other humans walked over and one of them pushed you into a strangely colored puddle and you writhe in agony as the puddle begun to slowly morph your body into a Protogen. They stood there, shocked as they didn’t realize that would happen to you.