10 Video Game Sub-Bosses With Unexpected Second Phases
1. Stray Demon - Dark Souls III (2016)
One of the core themes of the Dark Souls series is endless, inevitable decay, which nothing and no-one has the power to stop. And, since there are thousands of years separating Dark Souls I and Dark Souls III, you get to see many times throughout the latter game just how much this decay has afflicted the denizens of Lothric and Lordran.
In the first game, you come across three of the Stray Demon species, fighting each of them as full-fledged bosses. It's quite a nice burst of nostalgia, then, when you stumble into one in Dark Souls III's Farron Keep - although that's definitely where the niceness ends.
Demons are dying out, and this Stray Demon is implied to have survived since the very beginning. Its body is tattered and literally crumbling away, which, during your fight with it, makes for a very unexpected mid-battle twist.
If you choose to do enough damage to one of the demon's legs, it will completely shatter, leaving the Stray Demon largely unable to move. Don't think that's the fight over and done with, though, because now that it can't walk, it will buffet you relentlessly with the Boulder Heave pyromancy, which can absolutely obliterate you if you're standing in the wrong place.
There's also a certain added pressure to put this poor thing out of its misery now that you see it flailing around on one crumbling leg. The best thing to do is to end it, quickly, and not take it for granted while doing so.