We need to figure out where in the carnival he's being held. Him and the others. We need to know what we're getting into--or whoever goes in there is getting into. So a scouting mission first. Dark knows we're all coming this time. I don't think we have the element of surprise as easily as the last.
So find where they're at and then send in everyone who's capable of breaking them out while simultaneously dealing with Dark. He can't slip away this time.