GX was fun just because the writers were clearly drugged out of their mind when they wrote it.

Summary of Season 2's Plot:
Kaiba sent cards into space because, if aliens exist, he wants them to know how to duel. These cards were given "life" by cosmic rays and our hero Jaden has a good long talk with a humanoid dolphin space alien about how he has to save the universe.

Then there's Season 1 which had a real vampire babe as well as an amazon who one of the heroes got it on with. And Season 3 had alternate dimensions and a hermaphrodite and an Australian guy with a mystical eye who walks around with a crocodile on his back.