The father-son duo from Ventéclair indeed had already come to terms with the two Xiang Lords.
Liu Zhenshock was completely unprepared for this; he hadn't once hoped to reconcile with the two Dalisandros. Instead, he was constantly calculating how to deal with these two formidable rivals with the utmost speed.
From the perspective of magical principles, the arcane summoning enacted by the four great Demon Dragon royal families has a temporary combat contract effect. Even if the Xiang Lords were unwilling, they had no choice but to attack the enemy under the Demon Dragon summoner's will before the contract cooled down.
From a realistic standpoint, Xiang Lords, thunderous and cloud-soaring, had no reason to retreat without a fight.
