Here's that FMG the title promised.
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Celia had to jog to keep up with Rena as the half-orc stormed to the right-hand passageway in the antechamber, Copperpot trying to lift herself up on her breasts to see better.
"Hey!" The halfling called after them, "What's goin' on?"
"We're, uh, we're working on it!" Celia called over her shoulder as she followed the seething wave of orcish muscle down the last pathway. She barely had time to get her own light spell up, Rena charging into the darkness seemingly without concern for what lay in wait down the final hallway.
"Rena! Wait!" Celia called after her friend, the half-orc's shadow casting long down the hallway and into the darkness as Celia's light grew behind her.
"What for?" She snarled, not even looking back. "So they can get worse?"
"But-" Celia started, until a loud >chunk< echoed down the hallway, Rena immediately stepping back into a fighting stance as the loose flagstone she stepped on sank into the floor.
Celia clutched her staff to her chest, eyes darting back and forth as a deafening grinding sound reverberated through the corridor. Rena bared her fangs as two sections of wall began to grind and move, swinging on a pivot until the two sections of wall had come together in the middle, turning the straight hallway into a kind of hoop.
"...Is- is it over?" Celia asked, holding her light from one side to the other, trying to look into the side passages that had formed.
"...No," Rena said, her eyes narrowing. "Listen."
Celia stopped and focused, and her elven hearing immediately picked up the sound, a series of clicks and ticks against the stone that was growing louder and more numerous with every passing second.
"S-something's coming!" Celia said.
"Good!" Rena spat. "I was getting tired of bein' angry and not bein' able to hit anything!"
Celia bit her lip as the skittering noise got closer and louder, mentally preparing her strongest healing spell. She knew when Rena got like this, it wouldn't be the small, incidental wounds that a skilled fighter gathered on her; it would be a whirlwind of death and blood, and it'd be Celia's job to make sure Rena didn't succumb in the process.
"Rrrrr.... Finally!" Rena bellowed as a wave of huge beetles poured out of the two side-tunnels. Celia barely had a chance to recognize the the bright red and yellow-splotched carapace before Rena's axe came down on it, the beetle's innards escaping as some kind of pale orange ichor, spraying out of the wound with such force it splattered on the ceiling.
"Ha!" Rena bellowed as she swung again, cleaving two more beetles into similarly explosive pieces. "These things die good!"
Celia swallowed hard as she watched the battle. She was used to seeing Rena work by now, and knew the half-orc could handle herself, but the wave of giant beetles seemed to be inexhaustible.
"Behind you!" Celia called, seeing the leading edge of the insect tide began to circle around her.
"Rrrrgh!" Rena growled as she swung her axe in a wide arc with one hand, the axe heads slashing through several insects as she spun back into a fighting stance, bringing her armored boot down on one she had merely wounded and mashing its head into paste.
"Haaarg!" She exclaimed, her fangs glinting in the light as she grinned ferally. "Not gonna work!" She shouted, stomping on another beetle as she waded into battle anew.
Celia watched nervously, making sure none of the beetles hurt her friend. She saw their jaws snapping at her, but even as big as Rena was she was amazingly quick, and the few times she saw her friend get bit, it wasn't enough to pierce the heavy plate armor Rena wore.
"Hah! Yeah! Die!" Rena bellowed as she cut and sliced her way through the beetles with what seemed to be ever-increasing speed and ferocity, the pale-orange ichor now liberally splattered across the floor, walls and ceiling, Rena herself painted with the gore and viscera of her enemies.
Celia watched with concern, Rena's increasingly frenzied attacks troubling her. Rena was no subtle fencer, to be sure, but she looked like she was losing control, which, when throwing around an enormous double-headed axe, can be as dangerous to the wielder as their foe. Celia gasped when she turned to the side, her ichor-splattered face seeming off somehow. She edged to the side, watching as Rena swung her axe back and forth through the swarm of beetles, each death spraying more and more pale ichor around.
"Hrrgh.. Rrrrgh... Raaaah!" Rena bellowed, lifting her arms above her head and roaring. Even over the din, Celia could hear the sharp metal retort of her bindings coming apart, a couple plates of her armor hanging loose over an unmistakably larger frame. Rena seemed to be swelling right out of her armor, the already-muscular half-orc bulging and growing with every swing. Celia whimpered as Rena's hands grew out of her gauntlets, her nails lengthening into bestial claws. Her neck strained and bulged, the collar of her armor cinching tight around her burgeoning frame. She snorted and snarled at the constriction, heedless of its cause in her bloodlust but still slowed down by it. She roared again, Celia whimpering as she saw Rena's tusks surge in length, as wicked and monstrous as a dire boar's. Celia saw the beetles circling around behind Rena, opened her mouth to warn her friend, but the cry died on her lips, Celia's fear choking her off, not wanting to alert the swarm of monsters nor the new and terrible monster they seemed to be attacking.
Rena grunted in pain as a few of the beetles managed to sink their mandibles into where she'd grown out of her armor, launching herself backwards and slamming the offending beetles between her broadening shoulders and the wall. Celia cast a heal spell on her friend, her sympathy overriding her fear and just hoping that when this was all over there was enough of Rena left to remember not to attack Celia. Rena was thrashing back and forth, half-naked by this point as her leather and chain mail strained to contain her flesh. Rena was unrecognizable as a civilized race, looking more like an especially bilious ogre or troll as she thrashed back and forth, every motion a killing blow, the hallway painted floor to ceiling with beetle carcases and orange ichor. More than painted, even- she noticed as Rena thrashed around that the Ichor was beginning to stick to her, her ankles already completely submerged in the goo and refusing her movement outside her battle stance.
"Hrrrraaaagggghh!" Rena bellowed, her wild mane of hair matting to her skull as the ichor hardened, swinging her axe with all her might until it flew out of her hands, Celia ducking reflexively as the blade drove itself into the wall only a few paces from her. Celia cast another healing spell, unable to tell at this point where the beetles' blood ended and Rena's began, but still not wanting any lasting harm to befall her friend. Celia noticed the skittering sounds seemed to be dying off, no longer the continual wave of clicks but still a small swarm of them. Rena was becoming increasingly entangled in the ichor, but the beetles were lured to her, perhaps through the scent of their blood on her. Rena's hands were fused into orange mitts by the ichor, but still she pummeled them, crunching their bodies into the ichor soup. Her back, her knees, her elbows, she used any part of her able to move with any force, killing beetle after beetle until she wore their numbers down, Celia healing her when needed. Finally, nearly totally immobilized, Rena killed the last beetle by driving her tusk through its stomach and against the wall, leaving the hallway silent save for Rena's continual struggles against her bonds.
Celia swallowed, taking a step towards the struggling... monster, was the only word for it. Rena looked like some unholy crossing of a minotaur and an ogre, every line of flesh rippling with muscle, her head nearly touching the ceiling even though she was on her knees. She lunged this way and that, fastened so tightly against her bonds she could only really move her head and shoulders. Celia edged along the side of the hallway, careful not to touch the ichor splattered against the walls. She gulped as she approached her friend, Rena's snorting and huffing echoing down the hallway.
"R-rena?" Celia started.
"Hrrragh!" Rena roared, lunging for Celia and making her jump back against the wall.
"Rena!" Celia called out, tears brimming in her eyes. "Rena, it's me. Celia. Your friend..."
Rena glared at Celia, huffing each breath past her tusks, her enormous bulk taking up the entire side of the hallway. Celia tried to search Rena's eyes for any glimmer of recognition, but all she saw in the glaring eyes was bloodlust.
"I..." Celia started, looking down the hallway, to the caverns the beetles had poured out of. "I'll find the Maag," She said, reaching a hand out to Rena's straining face. "I'll... I'll fix this, I promise," She said, wiping tears from her eyes before she gingerly picked her way through the ooze, coming to the turned-out walls sealing off the end of the hallway. Slowly working her way around, she could see that the beetle nests had been completely emptied, every last specimen vanished from the warren as she stepped around the trick wall.