I'm using an N7 Demolisher with 6/6/6/6/0 (no Fitness). She is the keystone of this strategy, allowing endless grenade spam, tech burst and fire explosion setups, armor debuffs, and unlimited ammo for a party that's staying put. The other players are a Vorcha Soldier with Flamer, an Ex-Cerberus Vanguard with Slam, and an N7 Fury with Annihilation Field and Throw. The Asari Justicar with an offensive bubble and area reave is also a great choice for this strategy (as I'll demonstrate in the next vid), as are Infiltrators in general (but especially the Geth). Basically anything that will deal a huge amount of damage in an enclosed space (particularly to Banshees).