The mad bartender.
God I spent countless hours as a teen playing on a heavily modded and roleplay enforced ultima online server. I played Cedric Sartone, simple farmer turned tavern owner who eventually turned it into THE BEST PLACE IN TOWN. It was poppin every night, I was buddies with every adventurer, soldier, mage, druid, and ranger that played the game. After they went out and grinded their skills and did their quests, I was waiting for them with a warm fire and plenty of ale. I’d buy their ingredients and make awesome food and booze (max level cooking!) and was privy to all the gossip.
Little did they know I had a side hobby, I was brewing massive amounts of the most gamebreakingly toxic poison possible. For over a year I roleplayed with these people as a simple barman, pretended to be their friend and confidant, and then during a harvest festival where every player on our server was in attendance and I was payed to provide the food and drink… I poisoned every last morsel of food, every drop of drink and after the reagent delivered his speech and all of these fools raised their goblets for the toast and took that deadly sip, I stepped onto the stage and revealed what had happened. They where all going to die, and die they did.
Now this was a permanent death server (hardcore rpers mind you) and some had been playing those characters for 8 years and there they all were, collapsed and dying. Soon they were all unconscious, as you could only die if you went unconscious three times in one day or if a certain psychotic bartender came and cut off your head… which I did to every player in our group of 38. They were all there, and unfortunately so was I.
Revenge against what, you ask?
So the server had a pretty strict policy regarding pvp and pk, essentially the GMs had to determine if there was in character justification for any instance of disputed player killing, obviously my situation prompted a call for an investigation. I understood those rules from the start though, and I kept a written log in the game where I detailed my character’s building hatred of every single other player character in the world. He would keep track of every little thing from petty slights, to unpaid tabs, but more importantly I adopted the little mannerisms that people roleplayed to develop their characters into the madness of mine.
So Elias was always whistling, well I recorded how infuriating Cedric found it in his journal, and soon he had multiple journals packed full of a thousand reasons an unstable maniac could use to justifiably (re: server rules) murder anyone. The reagent who was also the server admin had some ornate cloak with a custom texture, so I wrote like three pages about how pompous it was, and extrapolated what kind of insufferable prick he must have been for wearing it.
I would just write one or two things down every day for over a year, so I had many books full for the GMs to locate in the tavern basement and read through. The result was that they found my massacre to be in good form and in-character, so the server was not rolled back and instead they decided to reset and implement a new landmass they had been working on. Some people were really pissed off, mostly a handful of the veteran players who had been top dog for several years in their little gladiator arena.
I only did any of it because my first character was murdered by some overzealous asshole who just used his character to project his inferiority complex. He killed me on my second day on the server because I wandered into the funeral of his friend (it was taking place in the middle of town and there was a crowd, of course I was curious) and because I was not invited and he was a known prick it was found justifiable for his character to kill mine because of the emotional turmoil blah blah. So yeah I said f*ck that, and rolled a new character who was ostensibly eager to please and non-threatening. I won.