The end of the cathedral got a fresh batch of motion-captured animations and, with them, a costume worthy of the fight underneath.
The new arsenal is properly animated. Swing a plain sword now and the Penitent works through three distinct strikes. They form a proper combo carved out of a dual-blade routine, and each cut has its own anticipation and follow-through instead of the same recycled swings. Pick up a mace or a hammer and the whole silhouette of combat changes. Blunt weapons stopped borrowing sword arcs and now smash, alternating overhead blows with a committed leaping slam as you attack. Sundering Leap got its body back too. Casting it used to fling the character through the air in whatever pose the legs happened to be in. Now the Penitent plays a full jump-attack through the flight, coiling, going airborne and striking down into the landing, so the slam finally looks like the thing the numbers say it is.
The Dark Lord learned to fly. Push the cathedral's end boss past his first phase and keep your distance, and he'll answer with a roar, a crouch, and a massive leap that carries him across the arena to land on you with a very large, very purple nova. The landing circle is drawn at your feet the moment he commits, and you have his whole crouch-and-flight to get out of it, so it's a dodge test you can survive. It still closes the gap in his kit. Hanging back at mid-range used to be the comfortable answer to him, and now nowhere is comfortable.
Smoothness always comes first, and the other half of the round is the one you'll hopefully never notice. Under pressure, the game now degrades its spectacle instead of its framerate. When the horde on screen grows past a certain size, faraway monsters animate at a reduced rate (the ones actually fighting you never do), and cosmetic effects and floating damage numbers thin out at the edges. All of it snaps back to full fidelity the moment the crowd thins. In a stress test with three hundred skeletons converging at once, the animation cost of the horde dropped by three quarters. The sparks are there to serve the fight.
The Dark Lord always fought like a threat, but he didn't always look like one. He was a very dangerous swordlord standing plainly in a very dark room. Now the moment he notices you, he dresses for it. A void aura wraps him, cold and creeping, the kind of effect that makes the air look wrong before he's swung once. His blade picks up its own glow, so every read comes with a light cue as well as a telegraph. Watch the sword as well as the stance. His Horrors used to just appear when he raised them. Now they climb up out of tears in the floor that open, disgorge something that used to be a knight, and seal behind it. All of it rides with him for the whole fight instead of vanishing after a hit, and dismisses the instant he falls.
None of this touches the numbers. The dodge windows, the phase gates and the fairness of every read are exactly what they were. This was a costume change for a fight that was already earning its keep. The thing at the heart of the cathedral was always worth the whole walk there to face, and now it finally looks it.