Sector 5

I use 501st rex lead, fives, echo, bb echo, and captian rex with my usual AA x 2, VA, Ruthless swiftness, and decelerator comp. After a few attacks fives gets a turn where he can call someone that drops an enemy under 100% tm and everyone gets over 100%. Then og rex can form up and give even more TM. bb echo debuffs everyone which brings them to 1% health, and og echo throws his bomb and kills 5 people. Works on the DC node (although often JKA blows up due to his bonus turn so it might only be 4 kills). So you get it in 10-12 battles either thru the zone as you go, or during the DC node. It gets a bunch of kills vs the iden miniboss as well. There are cheeses vs the iden miniboss that can get all 50 i believe, but I can't be bothered by that. Ive had my red create since monday without any cheeses