this is not a bug, they changed the multibattle a while ago to be intended for champ and food training.
any character not in the leaderslot gets replaced by champions in your "champion queue" if it reaches max level.
(which is why agent fox said this issue was resolved)
i don't like this type of multibatlle either, so i'd like to give suggestions:
- (easy fix)
if the champion queue is empty, dont remove champs with max level
- (medium fix, small UI change)
let the player decide which of the 4 slots are locked and dont get replaced by champions in the queue.
- (hard fix, needs discussion and UI changes)
make a champion queue on a slot basis (4 buttons for queue, one for each slot or something similar).
this way you can also replace the leader with aura champions. (this helps with people having a farm champ without an aura skill)