Would break a few chairs, a table, etc., and then go rush out with no plan besides to break the limbs of the rival who took their precious child away from them: Hoshi, Woozi, Mingyu, Dokyeom.
Goes through a bit of planning while gathering up a squad and traveling to the rival's headquarters, admittedly it wouldn't be the best plan but they would want their kid back as soon as possible: S. Coups, Joshua, Wonwoo, Dino.
Only the most precise planning would make them feel comfortable enough to go out and save their child from one of their most dangerous rivals, of course; only the best for their little angel: Vernon, Jeonghan, The8.
Would sorta, kinda, accidently, go into panic mode and wouldn't be able to actually do anything about it themselves at first because their planning is too unstable but would quickly ask for help to save the light of his life: Jun, Seungkwan.