you should put down defenders on the left side, and try not to put the snipers way ahead since the mages and the boss is going to target them quickly. you also have a severe lack of vanguards that generate DP for you, which makes the stage decently harder. in any case, don't pour too much resources on the right side of the map, just put enough, a good lane holding unit or a normal defender + a sniper is enough, your focus should be healing and guarding the left side
Better get some material and also join play event for get materials more easily Since more chapters more harder Operator need more buff and strong for e1 Also of struggling can't e1 4 5 or 6 star operator e1 3 star they will more help in early Seems you late much event till now I suggest more start grind just slowly go next chapter
