I need to make a correction and Idk where else to post it. So here it is. This says Curse of Anubis comes from Odion at lvl 21. I'm not saying that isn't true because I haven't even gotten Odion in the gate yet so Idk, but I got Curse of Anubis when I unlocked Ishizu Ishtar.
Well then your opponent is dumb. Mirror wall can be activated in damage step while this card cant.
uh.. currently the "battle position cannot be changed part" isn't working apparently. Not sure why, but every people I've faced recently were able to switch it back to attack position, especially when I had to pop it on main phase, because a sergeant electro was tryna pin it down. I'm certain this is a bug, because I've faced an opponent using this card several times and back then I couldn't change my monster's battle postions. AND NO, they/I were not using normal/gemini monsters.
I think is not a bug as is but something wrong with the way the text was interpreted, apparently this effect only last one turn as well. You can try it activating this in your main phase on your own monsters, you won't be able to change them back to attack except with card effects