Big, Green and Brutish the Orruks are a staple of Age of Sigmar lore, unlike their 40k cousins they are less about the whacky and more about the brutality (With Skaven filling in the Whacky niche) on the field of battle. With now 3 distinct subcultures (Ironjawz, Kruleboyz, Bonesplittas) and a fourth unified army brand (Big Waaagh) you can tailor your force to embrace whatever breed of Orruk you favour or create something truly special in a big combined force.
With each sub-breed of Orruk providing artistially and creatively distinct themes you can find one that speaks to you personally, from the cunning Kruleboyz lurking in the mists to the shamanistic Bonesplittas with their Waaghpaint or the wall of iron and muscle that is the brutish Ironjawz there is alot to explore and play around with