To complete this map i placed my weakest team at C1 and the rest at C3.The team at C1 need to be able to kill enemies and die at the boss.
At C3 your 1rst and 3rd squad will go up and the 2nd and 4th(helper) will go down.Now the most important is pray to RNGod that your squads get to the upper boss and be able to kill it.