He said that the Messenger of Allah ﷺ said, "Whoever lies about me deliberately, let him take his seat in the Fire."
حدثنا هشيم حدثنا عبد العزيز بن صهيب وإسماعيل حدثنا عبد العزيز بن صهيب
قال قال رسول الله ﷺ من كذب علي متعمدا فليتبوأ مقعده من النار
Its chain of transmission is sahih. Ismail here is Ibn Ulaya, and this hadith has occurred many times before.