Thanks a ton for all the guides Oyuki much appreciated mate~ Additional note if you have Typhon or Fiammetta or both and putting them on the top left with a healer (one facing to the right.), it will make the run even easier since not a lot of enemy will get close to your operators.
*Xy-axis vision: Range Matteo and all his gunners perform their straight shot, which is everything that is standing at same abscissa or ordinate as their location. - Put ranged dps on 2nd row at ur own risk, due to Matteo not only gun him down, but also *the explosive behind!* => Place healers instead on 2nd row, and ranged dps on 3rd row instead, with a tank right of him to shield him from minigun. - Position ur defenses such that they not only stay away from Matteo's bodyguard XY-axis vision, but also not trigger the explosives, while at the backdoor lane, keep *the wall near right blue box* healthy at all cost, u'll need more firepower on that lane in CM. - One by one, wipe out Matteo and his men. To prepare for 2nd phase, position ur dpses such that they separate Matteo from his bodyguards, or *pin him to the wall mentioned above* , rendering his smoke bomb and stun ammo useless, hit him with all ur might, use all the reinforcement devices to buy more time. - Whatever the method, do not try to stall Matteo with ur tanks at 6th to 8th column, you CANT waste his ammo due to 2 waves of bodyguards filling them full