The author invented that there was no card limit. Since Battle City there was already a card limit. Not bans, of course, but the card limit was there. That it is not mentioned is one thing but seeing the duels of the program it is quite obvious.
Apple Magician girl already. This means the cards from the last Movie are present in this universe. So Kaiba returned from the after life duel with Atem. Also that would mean Kaibaman got buffed to OP status.
Thanks for the chapter.
FinzRaizer