Thin Ice | Warrior Cats MiniGame (ON HOLD)

Round Six, Scene One

"Another one bites the dust."
A dark cat stalks up to the sleeping body of Darkmeadow. They watch as the black she-cat's flanks rise and fall, her breath singing to the beat of twilight.
The dark cat unsheathes their claws. Their eyelids flutter as they delicately run their claws deep into Darkmeadow's fur, with expertise that could only come from years of experience.
Darkmeadow's eyes fly open. She stares up at who she thought was her friend, her clan mate. With one final strangling, desperate gasp for air, she falls limp, and the perpetrator stalks away and lays back in their nest.

"Darkmeadow?" A deep voice calls. "Darkmeadow!" Stormbird races over, his whiskers twitching. He sees the pool of blood expanding around the dark she-cats head and steps back. "I knew it!" He exclaims. "I knew it!"
"What?" Olivespot lifts her head, blinking drowsily.
Soon enough all the cats are awake.
"I thought it was Darkmeadow," one says.
"Yes, me too."
They all share the overwhelming guilt that they weren't able to save their clan mate. They take Darkmeadow outside and bury her, sitting in crushing silence.

Who killed Darkmeadow?