Commander Kbaldir:
Like the other Seeds that have floated into Gracia, the easiest, and right now, only way to get to the Seed of Annihilation is by flight. You either need access to an airship or know the Aura Bird Transformation.
If you don't have an airship, the Dwarf they call Engineer Lekon below is who you should talk to. Officer Tolonis might also sell you one. As for the Aura Bird Transformation, I couldn't tell you how to learn it, I honestly don't know.
Nod in acknowledgement.