With a satisfied hum, Wing Commander Lightning Dust activated the last sensor crystal.

There, that will probably keep the eggheads off my tail for another few weeks. Lurching up, the mare rubbed at her stiff joints through the thick cloth of her Wonderbolt barding. While she couldn't complain about all the field work, spending so much time hunkered over and scooting through tight passages was never easy on a pegasus. At least this particular cavern was large enough to stretch her wings for a bit, even large enough that she'd lost track of her partner's light.

Hooves crunching over pebbles, she ambled over to where they had entered the cavern; another one of the slick chutes that wound their way through the caves. Perfectly round and nearly frictionless, the strange tunnels were just one of the many reasons she was down here. Another reason was the recent seismic activity, something that somepony was supposed to help her set up crystals to catalog.

"Sugar?" she called into the murky gloom, leaning against a boulder, headlamp casting out through the cavern. "Sugarglider, where are ya, girl?"

No response.

Lightning Dust snorted to herself. The mare was probably taking the time to nap. Given how warm and humid it was down here, she couldn't really be blamed for feeling the need for some rack time. They all felt it; the heat made them drowsy like cats in the sun. At least the base had air conditioning, a mercy this far underground.

After five minutes of waiting, she decided that Sugarglider wasn't coming back on her own, so with a bad-tempered kick to the ground, she opened her wings and jumped into the air. Slowly, the path they took retraced itself beneath the light of her lamp. There was the cracked stalagmite they'd documented. Over there, rock scuffed where Lightning Dust had dragged her horseshoe by accident. And by the small pile of stones, where they'd split up. She landed there, wing-beats echoing weirdly in the empty air.

Something tickled her nose. She sniffled, face scrunching up at the familiar reek. "Ugh, really? Sugar, now of all times to light one up?" she loudly complained. "I know it gets boring here, but this has got to stop." Following the scent, she stumbled over the rough terrain. Far up ahead, a lonely beam of light could be seen shining at the cavern wall from behind a thick pillar of stone. An cloud of irritation descended upon the mare, and she picked up the pace, ready to give a serious tongue lashing to the wayward subordinate.

Rounding the pillar, she began, "I swear to you, today is the last time I tolerate..." A solitary headlamp lay strewn upon the ground, pointing accusingly at the rock face of the wall, where another, hidden chute stretched further into the depths. "...this sort of thing? Wait, what?" There was still a slight haze in the air, the pungent aroma clinging to the pegasus' fur. She picked up the forsaken equipment, but instantly recoiled with a muffled gasp.

Now caught in her own illumination, she could clearly see the heavy red stains covering Sugarglider's headlamp.

Lightning Dust whirled on the spot, sharp golden eyes trying to burrow holes in the murk. Any thoughts she'd been having about going to sleep or returning to base quickly had vanished. She held herself poised, heart hammering in her chest and ears cocked to pick up the slightest of noises.

Not a sound could be heard throughout the cavern. It was as silent as a tomb.

After a moment, she decided she was alone. Lightning Dust turned back to the scene, following the beam of light from Sugarglider's lamp to the chute in the wall. This one wasn't on the maps. In fact, had she not seen the beam of light coming from behind the rocky outcrop, it would have remained concealed in the shadows. She had no idea where it might take her... but it was her best option.

The Wing Commander crouched at the entrance to the chute, her shadow casting itself into it's deeps. It was about as tall as she was, sitting flat. Her hoof was halfway through the portal when the sound of a pebble clattering across surface came from behind her.

She twirled, squinting warily into the light of the headlamp. "Sugarglider, is that y--ghhraaachk!"

A jagged black blur caught her in the throat, pitching her end over end into the chute. Her breath left in a solid rush as she slammed into solid rock and slid, hooves grappling uselessly at the slimy surface. Rocketing helplessly through the dark, she was abruptly spat out into open air, plummeting for a sickening heartbeat before tumbling to a rolling halt into something that splashed against her fur.

Bruised and dazed, she could only lay still while her mind tried to play catch up. The oppressive scent of copper was overpowering. She felt something hot and wet soaking through her barding. Groaning, Lightning Dust craned her neck, casting the crimson puddle she lay in with stark relief. At the very edge lay a ragged heap of fur and feathers.

"S-s-sugar... oh, no, no-no-no-noooo..." she mewled. "No...!"

Movement to her side. She tried to struggle upright, before something brutally slammed down upon her windpipe. Choking, Lightning Dust still hurled screams and abuse at whatever it was. The world was beginning to fade. Something hot and sharp was at her neck, sinking in, tearing. She felt herself falling.

The last thing before it ended was an utterly earsplitting screech, a streak of shadow that ripping through the air just above her. And only then -- finally, mercifully -- the pressure was gone, and Lightning Dust sank into darkness...

Author's Notes:

Eh? Eh? Eeeehhhhhhhh?