Six if you count the synthetic heroes. Sure they're weaker than Lloyd, Cain or this so-called Ultimate Hero, but they were still plenty strong. If they fought two-on-one they'd likely have been able to beat Sophia, who is herself seemingly one of the strongest beings on the planet.King's up to three world ending disasters in his employ to keep himself and the kingdom safe but keeps throwing them away because his feelings are hurt lmao
But yeah, basically the King could have had Lloyd, Cain and the three synthetic heroes without even needing to use this final trump-card of his and had all the power he needed to keep himself and his kingdom safe, easily able to deal with Eve and Sophia (if they became an issue), as well as Alice and other demons that might be hanging around and want to pick a fight with the kingdom.