I see, as i did really bad when the game started i have some event weapons that aren't MLB.
Garuda's hammer with no star, Typhon's lance with just 1, Jorm's hammer+medusa's glaive+rahab glaive with 2 stars.
At least i know that we"l have a rematch with advent events so i can MLB most of those weapons then.
But jorm's hammer will stay at 2 stars which is sad 'cause it's attack weapon.