Hiya fellow Lion fan!
I’m pretty sure Lion’s working on a “Code Lokyo” Fanfiction called The Mechanist on FanFiction.Net...summary pasted below:
There's a lot that happens. First, someone gets blasted back in time. Then that someone learns more about Lyoko and becomes dedicated to stopping XANA. And then there's the supercomputer nearly blowing up and then Ulrich and Yumi got...Okay, let's just start here. One day, Sissi snuck into the factory. Reviewing helps me write better.
Hope this helps :)