Bloodborne and Dark Souls director Hidetaka Miyazaki has revealed his favourite boss from the "Souls" series. And what do you know: it's from Demon's Souls.
More specifically, it's the Old Monk.
"I'm actually fond of a great many enemies and bosses from each title," Miyazaki told OPM UK (via PSU). "But let me weed it down to one: the Old Monk."
"This boss utilised a unique (and rather experimental) multiplayer system," the director added. "I remember facing a lot of opposition to realise the idea. I also designed the boss' head collar myself."
(Mild spoiler alert describing what makes the Old Monk so unique.)
You see, what makes the Old Monk so noteworthy is that he's not a typical boss, but rather controlled by another player (unless you're playing offline, in which case he's an AI). Here's how it works: the game finds another player looking to either invade a game or offer someone help, then spawns them in the Old Monk's throne room where they control the titular boss. Since he's a humanoid figure brought to life by an unholy gold headwrap, the person playing as the Old Monk will have whatever equipment and stats they had already. As such, no two Old Monks are ever alike (unless you play offline).
This could make the boss easy if you're paired with an unskilled player, but whoever gets summoned as the Old Monk gets a health boost during their duration as a boss. Plus real humans are likely to heal a lot more than AI, so if you're facing a rival of equal skill with a large bag of herbs, be ready to burn through your healing items as it might be a long battle.
My first time through Demon's Souls I thought the Old Monk's level was glitchy as it was the only boss that forced me to watch their entire intro cutscene every time. Weirder yet, this cutscene would start playing at different times as I made my way up the stairs to the throne room in which he dwells. It wasn't until years later that I read he was another player and that the unskippable cutscene was actually another player entering the game, which explained the cinematic playing seemingly arbitrarily.
Here's a video of the Old Monk in action:
Might as well ask, what's your favourite "Souls" boss?