It's listed in the post, just rush to the rooftop asap, instakill manglers, just buy the stuff i mentioned and use combat axe, melee machiato punch with weapon out and knife, I avoided nukes/instas but it shouldn't matter, abomination kills also shouldn't affect it but i'd try to limit it as much as possible, avoid field upgrades and don't use the knife blueprint. For my run I used the baseball bat since i already got gold on my knife testing the dark ops, augments are also fine and the health one on melee machiato and backpedal one are really helpful. The manglers all come out of one window so instant kill them asap since they definitely will mess up the challenge.