Varth Elmer
The grey orc were the direct spawn of Orcalacth the lord of Blood and Savagery. They came with him from the Dread domain.
Before then grey orcs didn't exist in the world, but even after the Liberation war, they inly managed to drive them to the edges and dark places of the world.
Over time their numbers grew and were culled and grew again. Just like goblins there was no getting rid of them. They were here to stay.
They were stronger and faster than regular orcs, the warriors were born among them more frequently. And they loved battle. They loved it.
Their whole culture revolved around battle, and some said that the more an orc fights the more powerful they grow. The foul power of Orcalacth made them perfect soldiers for war.
Even more so for grey orcs they knew how to slow down and think, they used strategies and plans instead of simply relying on brute force.