Lexx

Lexx was the owner of Lexx's Potions in Vir'Tol. He used to sell Antideflux potions who actually spread the Deflux decease.

In his workshop, he always had his assistent Var'Lek with him, who was his partner in crime. Due to their Deflux decease, a lot of innocent dragonborns were killed.

Once Var'Lek escaped from the Vir'Tol prison, Lexx also disappeared without a trace until Vianova managed to track them down due to tracks Lexx and Var'Lek left behind when they kidnapped Lu'Troh and Vianne.

In the Ruins of Wespor they had set up camp and experimented on other Dragonborns to try and get them to be more dragonlike again. After a lot of finetuning Lexx had managed to turn himself in to a red dragon-like creature who was able to fly and breathe fire. He burned down Arakzin with his newfound power for unknown reasons, after which Vianova tracked him and Var'Lek down, and killed them both, putting and end to their unethical testing on Dragonborns.

Fun Fact
Varis at one point worked for Lexx and helped the distribution of Deflux by being a potion courrier in Vir'Tol.