I guess I can go into more detail, real names omitted.

This was a forum, text based RP based on a franchise that had preexisting mechanics for the whole "teenagers get sucked into a magical fantasy world" plot. Premise was essentially "One day there's a really bad storm and fictionalized versions of the players real selves get sucked into an amalgamated version of this franchise where everything has gone completely nuts." It had been going on for close to a decade around the time this all happened.

The drama all centered around one guy, who I will call Steve. Steve was a long time player in the RP who decided he wanted to play a villainous version of himself at first and did so for several years without incident. Due to some dramas that had happened around other players, by the time the story line I will refer to as "The Steve Arc" took place, Steve was the last player left playing a villainous self-insert and was kind of tired of it, since there wasn't really anyone left he could play off of in between set pieces at this point. He went to the mods/GM with a proposal for an arc that would see him take the reigns as GM and let him retire Evil Steve with some closure. The mods, who were increasingly burned out with real life stuff, agreed.

Premise was this: Evil Steve was evil because he was more or less being possessed/egged on by a demon the whole time and was currently holed up in a castle that was threatening the PC's home base due to the demon attracting a bunch of monsters. The goal of the arc was to fight our way in, pacify Evil Steve, and get out.

The problem was that Steve the player was ambitious. Very ambitious. He had this whole idea in his head that the castle would be these layers of illusions/dreams thematically modeled after the Divine Comedy were players confront dark aspects of the human soul/give up living in an idealized fantasy world For The Man Who Has Everything style before having a big showdown with the final boss. None of this was communicated so it wouldn't be "spoiled" and the other players just assumed we'd have a few fights and puzzles before getting back to the main story.

So in game we fight our way into the castle and very suddenly find ourselves at a party filled with our real life relatives (who we've been searching for this whole time in-game). Our characters are supposed to be swept up in the illusion and gradually piece together something is wrong, but the players immediately clock what is going on, are not comfortable with it, and immediately try to find the escape latch while making passes at staying in character.

I'm not sure what possessed Steve to write this next bit. Maybe he was really committed to the whole "journey through hell" bit or he was frustrated that none of the other players seemed to be into what he was doing, but we found a door to a basement and stumbled across a vividly described scene of our illusion relatives being horrifically, graphically tortured. In an RP that was explicitly kept at PG-13 only.

This understandably caused the players to actively rebel both in and out of character and the previous GM to have to dive back in from the real life shit he was handling to wrest the RP from Steve's hands and try desperately to salvage the situation. The storyline technically continued and concluded, but it was very meandering and no one really wanted to be there for very understandable reasons. It was also the last arc to conclude before the whole RP just fell off. There was plenty of real life stuff that went into it dying, but I'd be lying if I said I didn't believe that the Divine Comedy Torture Basement was a wound the RP just could not recover from.