I'm running into this problem when sometimes when I do Krokopatra Master duel it redirects me to the exalted duel instead! :(
This is really annoying and my friends are a bit annoyed as well. Please fix this!
what level(s) are the friends you're going in with?
the dungeons claim they're for a certain level, but will scale to the level of the wizards in the dungeon. so, if you're level 45 and your friend is level 95, the difficulty will change accordingly.
i did the rattle master duel with a full group~ my wizards were both level 63, and my friend's 2 wizards were level 52 and 45. of course, the dungeon difficulty scaled up and basically became a toned-down version of the exalted instance, complete with insane pierce and the exact same cheats. the only difference is that the damage wasn't as high as exalted; that's literally it.
(good thing i was playing as myth and ice. so that i had plenty of shields (both universal and life/death specific) to go around and make sure that no one died)