Yumi, Aelita and others in “Unfinished Business”

Just what did you see?

Strange lights. Not natural at all. And those lines of code. I've seen them too much already.

X.A.N.A.? Didn't we destroy it?

It may have had a backup system.

Sure. but Lyoko, the Lyoko warriors...it's all over now.

X.A.N.A. may still be alive and you're just sitting here? Back then, you never had any doubt.