Dad's and Chen Yi's father unspoken rule is to never take anything from the past. You only need to take some notes not things. Three times Chen Yi's father broke that rule and dad cutoff his friendship with Chen Yi's father.
How did I get that Aztec CD so I can go back time? It is because that Chen Yi asked me to bring it with her. She lacked material to make Libra gold cloth for its shields and have no time to go to metalworks to build another one. So, even though the proportion is really different, she opted to use the CD for substitute. But when she chased me, she and me forgot all about the CD and when I was hit severely by the mass, suddenly it activated by itself and throw me into Xiapi. Talk about terrible luck, from shit to hell.