Just an artistic rendering of the Toxicist himself, Dr. Sullvian (full name Sullivan Roger D'Jonas). He is an Illager who attempts to sell "miracle cures" and "magical medicine" to trick villagers and non-illager aligned players to get themselves poisoned. The Plague Doctor costume is intended to hide the fact he is an Illager (given his gray skin and bushy eyebrows would be a dead giveaway). Dr. Sullivan is a calculated, calm man with a formal and charming demeanor and is great at marketing and scheming. In terms of (at least biological) age, he would be around 35-42.
  Rumor says that he is working on an actual cure for some unknown, spreading corruption and is begging for the Minecraftia Government to prepare for a possible pandemic, knowing they would not answer his pleas and being concerned for not only Illagerkind, but the entire Overworld. In other words, he may only be doing his crimes simply due to him listening to his clan, rather out of hate towards others. He is apart of the same clan as Morgan (the Leader and an Arch-Evoker), Rob (a Pillager), and Rose (a Vindicator).

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The Minecraftia Government is the In-Universe Equlaivent of Mojang in my AU (since it wouldn't be a video game).

I personally think the Illagers aren't truly evil and are just wanting revenge on the Villagers who rejected them (although not wholly good either, Sullivan is likely one of the more compassionate Illagers out there).

Sullivan has hair in the art but he would appear without it in the actual game if he was in it considering giving hair to Illagers and Villagers is just my personal stylistic quirk.

I might make a skin version of this sassy lad at some point later...