When your dragons start getting targeted by Inferno Towers set on SINGLE TARGET, drop your Freeze Spells. Do not drop freeze on infernos set on Multi Target.
If the town hall does not go down, drop your Heroes to take it out. If 50% is not reached, drop your Valkyrie in a corner to take out buildings. You MUST bring a valkyrie (there is no substitute) as it has high hitpoints and it does grouped splash damage, which helps take out corner buildings quickly.