Mikey's terrified scream rang out as it leapt at them. He shoved Donnie out of the way and both of them flew safely out of its path, the beast hitting the ground and continuing it's bound for the older brothers, a growl ripping from its throat. 

Apparently holding a grudge against Raph, it slammed him into a tree and tried to crush his head with its paw, interrupted when Leo charged and slashed at its side. It spun and lunged for the leader, jaw locking around his shell as it shook him enough to give anyone whiplash, the leader crying out when its grip tightened. 

"Let him go!" 

Mikey flipped onto its back and whacked its muzzle with his chucks, forcing the beast to release his older brother. It instantly moved to try the same attack on the jokester, but he was too fast for it and backflipped off it before it could touch him.

The beast was then assaulted by a furious Raphael and the hothead aimed to impale its side, only for it to spot him at the last moment and bite down on his arm, his brothers watching unbridled shock as it ripped it clean off. 

"Raph!"

The brother chorused their horror as the hothead stumbled back a few steps and then collapsed, the beast letting out a triumphant howl and advancing for his limp form.

Leo would have jumped to his fallen brother's defense if the sharp pain from the bleeding teeth wounds in his shell didn't halt his efforts and he painstakingly pulled himself to his feet, watching as Mikey dashed in front of their fallen brother, his thoughts swirling with disbelief. 

-This can't be happening. This isn't possible. This can't be-

A pained scream split the air as claws tore through plastron and his baby-brother fell next to the hothead, the echoing cry forcing the leader to his feet and to advance forward, his gaze straying with the beast's to his remaining brother. 

-No, no, no, no, no, no- "No!"

The vicious beast lunched as he charged and he could only watch as it shoved Donnie into the foliage and both disappeared from sight, the following agonized cry wracking his entire core, unwelcome tears streaming as everything seemed to come crashing down around him.

He steadied both katanas and waited for the beast to come back for him, the cold breeze biting at his wet cheeks as he remained motionless, his sorrow transforming into anger. Complete, terrible, unbridled fury. 

The beast lunched out from the dark and he ignored the flaring pain that came with his fluid dodge, the leader stepping back and allowing it to lunge again. His katana entered leg bone with perfect precision, the beast whining and stumbling, the leader yanking his scarlet weapon back.

"You killed them!" 

It spun as he charged and he sliced at its muzzle, the loud whine telling him that he'd hit his mark once again, his weapons shaking briefly as he fought to control his emotions.

"You killed them!" 

He darted to the side when it swatted at him and then hurried in its way when it tried escaping back into the forest, fighting not to look at the limp bodies to his side, new moisture wetting his cheeks. "You- You-" 

The beast roared and tried leaping over him, but he was prepared for it. He waited for the right moment and then leap upwards, katana passing through fur and entering its chest. He ducked and rolled to avoid getting crushed by the beast, stepping back and watching as the creature fell limp to the ground before the leader hit his knees, fists clenched hard enough to stop blood flow.

"Dead. They're- They're- I couldn't- I'm sorry. I'm so sorry."

Then the adrenaline wore off and he was hitting the ground, the darkness hiding at the edges of his vision swallowing reality and dragging him into its depths.