Falling in the Stars [a warriors mystery]

"Stay focused, Raccoonpaw! Execute the move again!"
The dark tabby tom nodded quickly, flattening his ears submissively. He refused to meet his mentor's scrutinizing gaze as he got into a battle stance. Raccoonpaw then leaped forward, feigning right and slamming into the warrior's shoulder. Before his mentor could react, he swiped at their face, ducking between their legs and kicking upwards. Raccoonpaw then rolled away, getting back into battle position.
The warrior did not seemed fazed, however, and they merely scowled at their apprentice. "Why did Jaystar and Ebonyfur give me such a foolish apprentice? You can't fight properly, and you don't hunt for the Clan! What use will you be to us in the long run? Do the move again! And this time, add the leap-and-hold!"
Raccoonpaw was usually an obedient fellow, listening to every word his elders said. But after being drilled to the point of having sore muscles and scratches all over, he had had enough. He snarled at his mentor challengingly, narrowing his eyes. "I won't do a thing. I refuse to suffer while you stand back and wallow in the glory of yourself. I've been working off my tail nonstop, and you still say I do nothing! I'm going back to camp, and you can't stop me!"
Raccoonpaw padded around his mentor toward the training hollow exit. He had set one paw outside the mossy hollow before he was intercepted. Foul breath latched onto his nose like sharp claws, and they dug deeper and deeper as his mentor neared him. "You're not going anywhere! If you won't follow my orders, I'll just be forced to get rid of you! I can't have defiant subjects in my future dictatorship," the warrior said with a smirk, the sound of their shrill voice making Raccoonpaw wince. "Y-y-you can't do this! We're Clanmates!"
Raccoonpaw's mentor roared in fury, knocking him over. "I can do as I please!" the warrior bellowed. "After all, I am the superior one in these parts. But I'll be kind just this once. Would you like your demise to come quickly, or would you rather-"
Raccoonpaw stiffened as long, dirty, curved claws poked at his neck. His mentor wore a proud, menacing grin that showed off sharp, yellow fangs. The warrior lashed its bushy tail, snickering as they pressed down on Raccoonpaw's throat. "-suffer?"
Raccoonpaw gagged, struggling to break free. He wheezed, flailing in the grip of his murderous mentor. He tried to hiss the word stop, but nothing came ot except the first consonant. His captor cackled at this, and their green eyes glinted with delight. "Suffer it is!" Raccoonpaw screeched as jaws clamped around his neck, and he was tossed across the training hollow. Blood oozed from his neck, and his leg was twisted at an odd angle. Before he could get up and try to flee, his mentor had him in their grip again. Raccoonpaw gasped as his windpipe was slowly and painfully crushed, and claws tore into his stomach. The young apprentice didn't remember much afterwards. All he remembered was hearing his mentor laugh maniacally as they vanished into the distance, and feeling such bitter, searing pain before his vision blurred and darkened...
Raccoonpaw was the first victim of the series of murderer in ThunderClan.


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Readers will be welcome to guess who the murderer is once the allegiances are posted. Pay attention to the clues, guys c:

Post the allegiances, I already have a guess. >;D