Are the descriptions of the Antichrist (Dajjal) as having a lion's head, a bear's hand, and a tiger's body, and that he ruled Britain 1000 years ago, accurate?

This statement is false; the Dajjal is a human being, and his form is like that of humans. This is indicated by the Prophet’s (peace be upon him) comparison of him to Abd al-Uzza ibn Qatan. His description was mentioned in a hadith (definition) in Bukhari: "Then behold, a corpulent, red man with curly hair, blind in his right eye." And in a hadith in Ibn Dawud: "The Masih al-Dajjal is a short, stout man, curly-haired, blind with a protruding eye." And in a hadith in Ibn Hibban: "The Dajjal is one-eyed, ajjan (one whose eye is prominent), fair-skinned, as if his head is an asalah (a snake)." As for him ruling Britain a thousand years ago, that is also a lie.