Seeing the sword covered in black flames heading straight towards him, Thousand Blades used all of his strength in an attempt to break through the power restraining him. While repelling the restraining force, he could feel that the power was weakening and he was just about to break away from it when he heard another cry in the sky, "Aaargh! I won't let you hurt him!"
After Yiren fought back, he was once again restricted from any movements but that clearly took a heavy toll on her as she once again coughed up blood, persisting even after that.
Yiren's sacrifice forced Xuefeng's target to stay in one place and he cleanly plunged his sword straight through him. Thousand Blades' eyes widened when his heart got pierced through, but deep down he didn't panic too much. As long as his head was intact, he could still regenerate himself.
