After Jusqua learns that Sorcerer requires 10,000 gil to lift the curse on cat he believes is Aire, he visits Thauzand's shop and asks him for a job. Thauzand seeing that the young man is in dire need of money, allows Jusqua to run his shop for a while. After Jusqua completes his shift, Thauzand allows Jusqua to run the shop at any time. After Jusqua and Yunita defeat the Sorcerer's puppets, Thauzand thanks them and tells them that the Sorcerer headed to Invidia. Thauzand tells the two to sleep at the inn and readies a ship for the next morning.
After the party is sent back in time, they arrive in Urbeth during the time of Beelzebub's plague. The party meets with Thauzand and discovers that his daughter, Eilith, is infected with the plague. Jusqua and the party agree to help and attempt to buy a Hi-Elixir from the Apothecary. After the party returns from the Hunting Caves with a Hi-Elixir, the party uses the Hi-Elixir on Eilith, but only manages to partially cure her.
Thauzand travels to the Tower to the Sky with the other civilians to confront the Apothecary. When the party arrives, Thauzand and the other civilians learn that Beelzebub has been fooling everyone in the town. After the party defeats Beelzebub and restores the city, Thauzand gives the heroes the Cape of Light. At the end of the game, the party goes to Urbeth and return the Cape of Light to him.
Thauzand's name is a play on the word "thousand". The Merchant Lords are named after large numbers as part of their association with money.