From Creatures Wikia
The Darkstag Norns are a genetic breed created by Narol. The Darkstags are a colored half-breed "created totally in game using mostly locally-born norns, with a few immigrants from the warp." The darkstags are a happy, peaceful breed. They tend to stay together, and get along well with each other, and with other norns and grendels. They require Fallow Norn, Zebra Norn, Treehugger Norn and C3 Bengal Norn sprites to display them properly.