Help. My Bl3 games keeps shutting down my xbox

Continuing the discussion from Ruiner Fight Crashes XBOX on Mayhem 10:
Every time i fight the Ruiner my Xbox would shut off about 20sec in. I tried uninstalling the full game and download it again but nothing is working. All my other games work fine but my Bl3. When I play around or do other missions on the game it works fine. I have my Xbox in a well ventilated space and no signs of dust build up. Also when Xbox shut off it is still cool to the touch. I don’t understand what is wrong.