Yeah it's practically impossible to defeat Gold if you don't have four players who know what the f*** they're doing.
Geth is easiest. Quarian Infiltrator and Sabotage does great work. I use a shotgun. I don't do a lot of damage, but it's a fantastic support role and I've saved the day quite a few times before.
Also don't forget that you have those one-use items on your d-pad.
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~Halo Live, fight, survive, as a family.
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