Master Poisoner

""Sadi could poison one person at a banquet with a thousand guests.""

- Garion of Riva, The Malloreon

A Master Poisoner is a character who is an expert in the preparation and administering of poisons. He can tailor a toxin to any situation: to paralyse, to knock out, to kill, or even other, more exotic, effects that others would consider beyond the realms of conventional toxicology.

Related to Poisonous Person, but the Master Poisoner usually doesn't produce toxins within his own body.

Anime & Manga

 * In Inuyasha there are several, including Sango, Yakorou Dokusen and Mukotsu from the Band of Seven who almost succeeded.
 * Himeko of GetBackers, and also her brother.
 * Abe no Kaii in the Lone Wolf and Cub.
 * The herbalist Pink, of the Sibling Team of Pink & Link, from Ranma ½. The former specializes in plant-based poisons, the latter, in medicines, but both of them are deadly at their craft. Kodachi Kuno is a lesser example.
 * Megumi Takani of Rurouni Kenshin could arguably be considered this in her Dark and Troubled Past. She was supposed to be training in medicine, and though she gained medical knowledge, she ended up being used to produce opium. She knows all about different poisons, but now cures them (among other roles befitting The Medic).
 * Due to his...unusual...hobbies, Earl Cain Hargreaves of Godchild is very knowledgeable in-and collects-poisons.
 * Sasori from Naruto. All his weapons are equipped with a very special poison he created himself which makes the victim suffer extreme pain for three days before dying, if he decided not to finish the victim off in the first place.
 * He learned this, and his puppetry, from Chiyo. Chiyo's poisons during the 3rd ninja war were often cured by Tsunade, whose friend and pupil Shizune is also a poison master.

Comic Books

 * Mejai from Le Scorpion
 * This was Poison Ivy's original schtick in the Batman comics, before she became a Poisonous Person.
 * Another Batman villain, The Joker, was a prodigy at this. In both the 1989 movie and the animated series, he developed "binary compounds" by which he could succeed in murdering victims with the second exposure, thus appearing not to have been directly responsible for their deaths. The man's chemistry skill is such he can create incredibly toxic compounds out of nothing but the contents of a janitor's closet.
 * Yet another Batman villain, Scarecrow, concocts fear toxins to give targets nightmarish hallucinations.
 * Doctor Poison from Wonder Woman.
 * Stinger, a minor foe of Green Arrow and Black Canary.
 * In the Angel Gang from Judge Dredd's rogue gallery, this was Fink Angel's specialty skill.

Film

 * The lead character in The Young Poisoners Handbook fits this to a T.
 * He's based on Real Life Serial Killer Graham Young.

Literature

 * Thomas Griffiths Wainewright is a master poisoner, according to Oscar Wilde's essay, Pen, Pencil, and Poison.
 * Lord Downey, head of the Assassins' Guild in Discworld, is rumoured to be this. There is no record of anyone Lord Downey may have wanted to inhume ever being poisoned, however. Which may just indicate that he's really good at it.
 * Sadi of Nyissa in The Malloreon. In fact, most Nyissans, though Sadi is a standout. He's also a master pharmacologist, a drug-dealer, and an all around useful guy, who has weaponised a wide variety of toxins and chemical concoctions, and fights with Poisoned Weapons. Surprisingly, he's one of the protagonists, and one of the rare fictional examples of a truly Badass eunuch.
 * The poisoner from Best Served Cold by Joe Abercrombie, Morveer.
 * This is a large part of Fitz's training in Assassin's Apprentice, the first book of the Realm of the Elderlings series.
 * In Dune poison is almost an accepted science.
 * Farran the Poisoner in the Redwall series. He never speaks, never shows any emotion (except at his death) and ends up causing a bit of havoc (being responsible for the deaths of two hares and poisoning the entire food and drink supply of Salamandastron, before being Hoist by His Own Petard when Lord Urthstripe crams all of the various poisons he carries down his throat.
 * In The Demon Princes, the planet Sarkovy's Hat is brewing and finding creative ways to administer poisons. The higher ranks of their grand masters can be Poisonous Persons, although in a touch of realism, these people tend to die rapidly themselves. Hero Kirth Gersen spent several instructive years there, to the point of being able to outwit and infect a rival Master Poisoner.
 * Durzo Blint, of the Night Angel Trilogy is a wetboy ("Wetboys are to assassins like a tiger is to a kitten.") who excels at poisoning.
 * One of Fu Manchu's numerous nefarious talents.
 * Hestera Spikesap from The Edge Chronicles is a master of potions one and potions all, from elixirs that revitalize the body to powerful alcohols, but poisons of all kinds appear to be her greatest talent. She knows how to give disobedient servants bad stomach aches, and
 * Jeff Pride, hero of Azor!, brought what he believed to be a poisoned murder weapon to American intelligence. The poisons expert they called in scoffed at the idea that the tiny amount of toxin this weapon could carry would harm anyone. Until Jeff mentioned that the suspected maker of the device was Gitano (Spanish Roma). The expert promptly turned pale and changed his mind, agreeing this gadget could be super-lethal. Gitanos can make poison out of ingredients no one else could, he said, and now he was nervous about having even examined the thing....

Live Action TV

 * Livia, and later Agrippina, from I, Claudius. Livia's simple "Don't touch the figs" will send chills up your spine.
 * A one-scene wonder has Livia talking shop - by which we mean multiple murder by chemical means - with Martina, another Master Poisoner, played by the same actress who portrayed the cheerfully insane Nursie in Blackadder. The two debate the relative merits of different poisons and their antidotes over dinner, only for Martina to go white with fear at the sudden thought that Livia might have poisoned her. Livia laughs it off, but the viewer expects Martina to drop dead at any moment, and her ultimate fate is left unspecified.
 * Locusta in the Doctor Who serial "The Romans".

Tabletop Games

 * Dungeons & Dragons Assassins in all editions that has them as a class or kit.
 * Dragon (magazine) #39 has an article titled "The Anti-Paladin NPC". The Anti-Paladin is an aficionado of the art of poisoning, who considers poisoning to be an esthetic pleasure and a means of artistic expression. They have collections of poisons that they use on a regular basis.
 * Dark Sun bards are known for such a practice and learn to prepare and use more poisons with the level advancement.
 * In the D&D lawyer friendly spinoff Pathfinder, a number of classes such as rogues, assassins and the currently experimental ninjas are proficient poisoners, but it's the Alchemist, which can not only make poisons, but becomes completely immune to them, can refine them into a more deadly, harder to resist form, make them last longer on the weapon and make them in a fraction of the time with reduced material costs.
 * The Dark Elves from Warhammer Fantasy Battle are perhaps the foremost poisoncrafters in the setting, though the Skaven are also very good at it, and the Chaos Gods Nurgle and Slaanesh have several excellent poisoners amongst their followers.
 * One of the skills that fits under the Scorpion Clan's hat in Legend of the Five Rings. The Shosuro family in particular kept large gardens full of various plants that could all be turned into some kind of poison.

Video Games

 * In World of Warcraft, one of the abilities of the Rogue class is applying poisons (usually to their own weapons). The Assassination talent tree partly focuses on this particular ability. One of the talents in the tree is literally called Master Poisoner.
 * Hunters, meanwhile, poison with certain abilities like Serpent Sting. They can also set a trap with venomous snakes.
 * Some bosses definitely qualify. Cataclysm has introduced Vanessa van Cleef, who administers literal Nightmare Fuel to all party at once, and renewed High Priest Venoxis, with extra ham.
 * King Hlaalu Helseth of Morrowind is rumored to be the most talented and subtle poisoner in the world, although there is no concrete evidence to support the claim. Admittedly, the lack of evidence could simply speak towards his subtlety.
 * A Master Alchemist in Oblivion can produce a staggering variety of poisons with Standard Status Effects beyond all those listed in the trope definition. Though poisons in-game aren't as instantly lethal, a full stack of damage-over-time effects make it a foregone conclusion. Replace one of those with fatigue-drainer, and you can safely look your opponent in the eye as it dies.
 * Command & Conquer: Generals has the notorious Dr. Thrax, one of the GLA's generals. Under his command, almost all of the units that normally use high explosives instead use a biochemical cocktail called Anthrax Beta/Gamma. He got his degree in bacteriology from a mail-order college.

Webcomics

 * Axe Cop is a rare heroic example.

Western Animation

 * Batman: The Animated Series: The inevitable showdown between the Rogues Gallery's two master poisoners occurred in "Harley and Ivy", when The Joker came looking for Harley Quinn after she had gone to live with Poison Ivy. Joker had his goons grab Ivy and sprayed a mist from his poisonous lapel flower in her face. Being a Poisonous Person, of course, Ivy was completely immune.

General

 * Lucrezia Borgia is often portrayed as this; see History Marches On for a discussion.
 * All of the Borgias had the reputation of poisoners, not just Lucrezia. It was probably untrue of Lucrezia and Rodrigo ( AKA Pope Alexander VI), but likely enough in Cesare's case.
 * Locusta, who may have assassinated the Roman Emperor Claudius and several other people. She was rewarded by the infamous Emperor Nero.