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A 3-person fireteam is best, with add-control sub-classes. Warlock Stormcaller, Titan Sunbreaker, and Hunter Nightstalker would be ideal. A fireteam with those 3 subclasses could chain their supers together to spam the adds and generate orbs for each other.
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Honestly, a balanced fireteam of weapons bubble, trance lock and tether. You wanna kill everything as fast as possible.