Mithrandir desires to return to Minas Tirith and spend some time studying one or two matters that trouble him concerning the state of Agarnaith.
'The creatures that walk in Agarnaith and the vegetation that grows there suffer from a rotting disease; worry has begun to gnaw at me concerning this disease. There are scrolls and tomes within Minas Tirith that may dispel my concerns. I hope they do. I will need your help, ${PLAYER}.
'The waggon-driver, Rathnor, prepares soon to leave. He will bring you to the city, with some others, and Shadowfax will bear me alongside.'
The waggon-driver Rathnor can be found near the Black Gate.
Mithrandir is in the First Circle of Minas Tirith, just south of the entrance to the city.
A book concerning the Great Plague and a scholar willing to part with kingsfoil must both be found within the Houses of Lore, on the southern side of the Fifth Circle of Minas Tirith.
Ayorzén is on the parapet overlooking the city on the south-eastern side of the Fifth Circle, in Minas Tirith.
Mithrandir is in the First Circle of Minas Tirith, just south of the entrance to the city.