Adar was a mysterious individual of the Second Age who was referred to as Lord-father by Orcs presumably because of his status as one of the Moriondor, the first Elves to be captured and tortured by Morgoth. The fallen Elf was once Sauron's lieutenant, but he grew disillusioned with his master's cruelty towards the Orcs and betrayed him. In the end, he was betrayed and slain by his own "children", who embraced Sauron as their new Dark Lord.