You can select new squadmates when you begin this assignment. You still face synthetics in this assignment, but unlike in the other assignments of the DLC they're just regular machines, not geth. Aside from choosing the usual counters in Overload, Disruptor Ammo, or AI Hacking, consider having anti-armor capabilities as well: Incendiary Ammo, Armor-Piercing Ammo, Incinerate, etc. Stasis has some utility here as well because of its insta-kill ability against flying enemies, which can help simplify a major battle ahead.