After Jonouchi's win night falls! Yugi and company forgot to get any provisions etc, so Mai ends up feeding the gang, and shows her true colors. Turns out her bold unapologetic ruthless persona she displayed up to this point was just a front she puts out as a duelist. She is a much more sympathetic character when she opens up. She has layers, I guess. She open's up to Anzu in general, and tries get Anzu some alone time with Yugi. Which only leads to us seeing how insecure Yugi is about himself, and his living in the shadow of his other self.
So yeah, character interactions and development is what the Yu-Gi-Oh manga is all about (minus all the games and all). The anime literally strips everything away. Crazy right?!
Anyway, in the second half another player killer appears! He has defeated Mai, and taken all of her chips, but Dark Yugi is quick to the rescue, and challenges the guy for Mai's sake!