I don't think the shadow can ever have first maneuver action. Any kind of shadow threat removal will work,
19P18 at an underground packs a major punch too, but isn't enough to rely on. Any form of shadow phase possession discarding, ie:
Corsair Marauder,
mumak rider, works well. I wouldn't recommend trying the
GATS/Hate/Orkish lackey because the only way it's really going to do anything is with very few threats and if you have a lot he'll leave you with maybe one
orkish lackey to squeeze a wound off and it won't be enough. So ultimately I'd recommend using 3x
Demon of Might, 4x
Orkish Lackey, 4x
Ships of Great Draught, and as many underground/battleground sites as you can find and something to help cycle and reuse minions.