Velen 2
Cornelius 3
Anduin 3
Xyrella 1
Tirion 2
Sinestra 2

Open Velen, Corn, Anduin. Tirion has ashbringer for buffing up Sinestra. Sometimes if you are able to get a few blessings onto Sinestra it can win Sinestra mirrors too.

Comp is good at killing reds and then Sinestra can usually hold a draw or win.

I only started Mercenaries a week ago so comp is not maxed yet but is still finding success.