This petitioner you already know - it's Burrogh. He managed to leave Barheim Passage and now he's sitting in Nalbina by his stall. Unfortunately some kind of monster prevents caravans carrying his goods from getting to Nalbina. He asks you to get rid of him.
About 37 000 HP
Resistant to Libra
Atomos prowls in the north-western part of Mosphoran Highwaste just before the entrance to Salikawood.
Nothing in particular - kill him as fast as you can. I don't know about any special ability of this mob. The only obstacle here ma be Vultures that are flying nearby. Just kill those closest to the enemy before you start the fight.
Bounty: 1800 gil, Gaia Rod, Diamond shield.