Take Your Time On Chapter 7
The Battle of Barious is brutal. Especially if you shun lancers and engineers. This is one of the missions where having these bad boys on the field is vital to survival. Timing also plays a huge part, as destroying the tank is at first only possible after it fires its main gun. And it only fires its main gun every so often. Valkyria Chronicles sure likes big tanks with big guns, don’t it…
Here’s a nifty trick: the radiators that make it vulnerable when destroyed disappear until the next gun discharge after you take one out. So get your lancers to reduce all of their health to the point where one more hit will do it. Then finish off one, and from then on a single hit will be enough to take out the rest. Once this is done, have your engineers refill your lancers as they knock out the tank in one or two turns.
But sometimes Selvaria just murders everyone, so don’t get too mad if this doesn’t work.