His senses were dulled to a squint, open only enough to catch the sign to act. Not any moment would do. The sorceress believed him to be under her spell. Rhainyr knew how to defend his mind from even the likes of demons. He followed her commands numb. He nestled his soul in a hidden alcove of his psyche where it would watch and wait. No emotion was allowed to sway him or out his hidden soul. Rhainyr kept his mind emptied to prevent any distractions. He’d ignored the sounds of the revelers, the incantations of the sorceress, and the songs of the twins.
It was if eons had passed in a dreamlike existence. Time was either long or nonexistent in this place. He knew his psyche was being drained. His muscles weakened. His physical form was bound and stiff. He was tied so he could have left every muscle loose and he’d still hang in his supplicant pose. However he kept his muscles taught so that when he acted there would not be a twitch to reveal his wakened strength. The strain on him was not physical. The sorceress fed on him like a mammoth leech whose mouth sucked directly from his heart.
His friends weren't coming. Or they weren't here. No one would save them from their fate. Was that the clamor of battle at the edges of his senses?
A swift motion and the gleam of a blade was the moment that roused his lifeblood. An epoch passed as the blade made a sweeping arc to its destination. Even though Rhainyr was primed and waiting for this moment, it felt as if he were a gnat trapped in amber. The expanse between himself and the arcing blade was too far to surmount in the few heartbeats left for the blind victim of the blade. Rhainyr reversed the forward surging motion of his muscles. The siren crumpled under the biting sacrificial blade. Blood pooled around her. The sacrifices had begun. The first was Ilsis the Dark. She was the tainted mirror image of Eloise. Who he’d fallen for that fateful night in the bog outside of Valbone. Instinct told him his love was pure and virginal. His instincts had kept him alive. He trusted them thoroughly. Never before had he felt the need to know someone even though conditioned reflex pushed her away. It was if, in those following hours, he had become a different person. He experienced something unknown to his character and that had changed who he was.
The dagger was raised across the witch’s chest to strike at the twin on her other side. Eloise was oblivious. She was lost in her reverie of song. Her innocence was just a tool to these folk. She was a caged song bird in an invisible coop about to be struck down for her grace alone. Had Rhainyr cared to reflect, he might have known he yearned to save the innocence he’d lost before he’d ever known it.
Rhainyr was tethered to her physically and spiritually. He used those binds against his captors. Before the witch’s final blow landed, Rhainyr drove his every sinew to the same purpose. Twisting the cord about him thrice in a whirl. Eloise was jerked forward. The dagger cut her shoulder in its heart seeking arc.
Then a wraithen power clenched around his neck and lifted him from his knees. He ceased his struggles. After withdrawing his resistance, he shifted his weight and corkscrewed himself in one last surge towards the ghostlike power that held him. It crumpled. If she hadn’t the collapsed the rigid force of her ghost hand, she’d be driven backwards into the flame. He would have been just as content with that result, however he continued his course soaring forward. His head, torso, arms, and hands were all still tethered to the ram’s skull in a web of cordage. Rhainyr saw the witch’s shock, but knew her dagger still thirsted for sacrifice.
He saw the ritual dagger in flight as he charged. It sunk somewhere between his ribs as he hurtled across the dais. He sailed on using the horns as if they were his own to gore the witch with his full fury and weight.
Her lifeblood fell over him. Her gauntleted hand tore at him. Her legs kicked trying to over balance him. Her guttural curses faded and her body fell slack. Rhainyr grew aware of the silence around them. The congregation’s songs and music had ended. He was blinded by the witch’s emptied life force though he sputtered to be free from it. He knelt once again. It was not in supplication this time. He steadied himself before bucking the sorceress off his horns like a triumphant stag. She fell into the ceremonial brazier’s fire. There were no shrieks of pain. Life had already fled the witch’s form. He only heard Eloise’s sobs. He knew she was at her sister’s side even though he could not see her.
The ritual blade bit at his chest with every breath.
A really exhilarating conclusion, though I dearly hope there's more to come! The abstract nature of Rhainyr's psyche really came through, in the moment of the ritual, very well done . A few typos here and there, you might want consider going through it one more time.