I recently tried an old Dual Brian team, which got completely shredded by a Maw. Having only one slow source of albeit ridiculously high damage is too much of a liability against devour teams.
Instead of wiping both Brians in favor of multiple damage sources, I opted to cut one Brian and speed the damage up with a second mana feeder.
Thrall has been on my radar for a while as a gem destroyer that scales with magic. Between his third trait being magic link and a +2 purple banner, he fills up all 6 mana in one turn. Use Thrall to quickly fill Gorgotha, who wipes the whole board with any sort of magic boost. Once Brian boosts magic, these two do not stop filling each other every cast.
Besides skulls being matched and destroyed, Crimson Bat is still the only major source of damage. It is important to get him rolling as fast as possible, especially against devour teams. If you are lucky and get a quick magic boost from Brian, it should only take a few casts from bat to wipe the enemy team.