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A Mahdi or Seeker is the leader of a Tuatha'an or Tinkers caravan (also known as The Traveling People).

The Mahdi is responsible for various Tuatha'an ceremony, including the greeting of visitors.

The formal greeting and response would follow the pattern below:

Mahdi: <presses both hands to chest and bows> You are welcome to our fires. Do you know the song?

Visitor: <same bow> Your welcome warms my spirit, Mahdi, as your fires warm the flesh, but I do not know the song.

Mahdi: Then we seek still. As it was, so shall it be, if we but remember, seek, and find.

[edit] Known Mahdi

• Raen

[edit] Seanchan

Seeker can also refer to a Seanchan Seeker for Truth. They are a detective/spy force employed by the Empire. One notable Seeker named in Crossroads of Twilight is Almurat Mor.