Ryoumen Sukuna (Jujutsu Kaisen)'s true from, first shown on chapter 3 of Jujutsu Kaisen, depicted as having Extra Arms, Extra Eyes and a Stomach Mouth.
Do not tag when Sukuna is possessing Itadori Yuji's body, or when the form's key features are missing, specially the Extra Eyes on the right side of his face. The main distinctions between Sukuna's true form and Yuji's possession are his Extra Arms, Stomach Mouth, Plug (Piercing) earrings, and mainly his overall size and hairstyle, his hair being wavier than Yuji's Spiked Hair.