I think this probably isn't the final battle. I think the heroes will get the upper hand against the triad after Asta and Noelle's teams arrive. In the meantime Mereoleona reduces the demon to a pile of bones, paralleling her famous ancestor.
But then somehow the devils will break out of their hosts and be fully unleashed and completely overwhelm everybody inside. But then Mereoleona will come in and fight all 3 of them at the same time. She says she'll buy them one week.
Everybody else runs away and Asta, Noelle and Yuno train somewhere and fully master anti-magic mana zone, ultimate magic and elf powers respectively.
After a 7 day timeskip we see Mereoleona who's badly injured still standing and about to be hit by an extremely powerful combination magic spell from all 3 devils at the same time. Suddenly Asta, Noelle and Yuno appear and block the attack.
Final battle begins.
While the battle is going on Mereoleona recovers and saves Yami and William with a flaming lion punch Digimon style.
But then somehow the devils will break out of their hosts and be fully unleashed and completely overwhelm everybody inside. But then Mereoleona will come in and fight all 3 of them at the same time. She says she'll buy them one week.
Everybody else runs away and Asta, Noelle and Yuno train somewhere and fully master anti-magic mana zone, ultimate magic and elf powers respectively.
After a 7 day timeskip we see Mereoleona who's badly injured still standing and about to be hit by an extremely powerful combination magic spell from all 3 devils at the same time. Suddenly Asta, Noelle and Yuno appear and block the attack.
Final battle begins.
While the battle is going on Mereoleona recovers and saves Yami and William with a flaming lion punch Digimon style.