Hazrat Mahdi (as) will have a mark (scar) on his forehead

Humran bin A'ayan says: I asked Imam Muhammad Baqir (as): ... THERE WILL BE A MARK ON HIS [Hazrat Mahdi’s (as)] FOREHEAD, and a mole on his face. (Sheikh Muhammad ibn Ibrahim Numani, al-Ghaybah al-Numani,xmqp. 252)

Humran bin A'ayan quotes Imam Muhammad Baqir (as) that he said: "... Hazrat Mahdi (as), WILL HAVE A MARK ON HIS FOREHEAD, and his face will be beautiful..." (Sheikh Muhammad ibn Ibrahim Numani, al-Ghaybah al-Numani, p. 252-253)

Abu Bashir says: Imam Muhammad Baqir (as) or Jaffar Sadik (as) said: "There are two signs of the Qaim [Hazrat Mahdi (as)]. There will be a mole and A MARK ON THE HEAD ...” (Sheikh Muhammad ibn Ibrahim Numani, al-Ghaybah al-Numani, p. 253)

This mark on Hazrat Mahdi’s (as) forehead is probably A SCAR. In addition, the use of the word “mark” in the hadiths, instead of “mole,” suggests that the mark will be lighter in color than a mole.