They turned Moons into Ork Death Stars, they had a Temple Gargant that dwarfed Imperator Titans to the point of having Gargant (Reaver warlord sized titans) as door guards for its inner Sanctum, destroyed a Imperial super weapon, and generally crushed Imperial forces (a Primarch was also included)
It seems Ork Kultur evolve to a point where needed orks like diplomats and such just appear (like orks do) based on the size of their empire.