Our Prophet (pbuh) informed 1400 years ago that Hazrat Mahdi (as) would appear after the passing away of the King of Saudi Arabia

Hijaz (Saudi Arabia) will be ruled by a man whose name is the name of an animal, when you see him from a distance, you would think he has a lazy eye, and if you get close to him, you do not see anything in his eyes…. Give me the good news of his death, and I shall give you the good news of the appearance of the Hujjah (Imam Mahdi).

Two Hundred and Fifty Signs, sign number 122