I'm playing on the PS4 Remastered version and just finished chapter 7 where I had to fight the emperor's huge tank and then Selvaria showed up.
What I don't understand is why neither her nor the tank made any real effort to kill me. They had the max action points and could've wiped out my team 10 times yet chose to end their turns. I parked my tank near a rock wall and hid units behind once I realized she couldn't hurt it but she made no effort to simply walk around it despite having enough AP to traverse the screen.
I'm guessing the game imposes some sort of restriction in certain scenarios.