Raubahn is Captain of the Immortal Lions and is a mission boss in Final Fantasy XI: Treasures of Aht Urhgan. He is fought in the first half of the mission battlefield Nashmeira's Plea. Raubahn is fought alongside Razfahd and has to be defeated in order to progress to the second phase of the battlefield where players fight Alexander.
Raubahn is a blue mage and will only use the spell Eyes On Me. Due to the fact that he can reraise twice in this battlefield, he must be fought a total of three times. In his second and third "lives", Raubahn is able to use Azure Lore, which greatly boosts the damage dealt by Eyes On Me.
Raubahn gains resistances to specific damage types depending on the kind of damage that was used to defeat him in his previous "lives".
For example, defeating Raubahn primarily using magic in the first "life" grants him 50% magical damage reduction in his 2nd "life". And if he is defeated primarily using magic in his second "life", he will be immune to magical damage in his 3rd. As such, it is important that players vary the damage they use to defeat him on his different "lives".