The sniper made a huge difference. Using it after extreme evasion is game changer for the pillars and boss. Thanks to this video I was able to finally get by 15-1. I spent a week trying to beat it and this actually helped. I think the Sniper was only at level 37 but I have a lot of duplicates for it.
I m LV 49 and for clear this chapter i need only the Last two Missions. My Power ievel ist 120k. It is hard but possible, Just Play good. For now i need to wait for LV 51.
Without the group up skill, it's gonna take extra long to clear the mobs. Beside the mc's skill some character like the dark SSR girl and wind SR SR girl also has mob pulling skill.
Lock on enemy with right analog stick (target icon on phone). Lock to them before you make the shot and it won't miss. Auto target doesn't work the well from my exp.