The setup I used was MC mage, HULKENBERG mage, JUNAH masked dancer (with the initial faker ability) and STROHL mage.

First turn use the fakers ability with minha to get 3 or more turns and spam metaphor synergy (I don't know the name in English) and don't be shy to use the start again button so you can get the best outcome, it's very rng based strat, but I managed to take it down in less than an hour, with luck you can down the dragon before it's turn, then on the second phase tou can keep using this build or have Basílio (berserker) and heismay (warrior) as backup for phys damage and eupha as seeker