Apologies for the openly military science fiction intro to this erotica; I have a problem. I added sweat and musk play because I have more than one problem. And yeah, one of the three in this threesome is trans, but that's not a problem I just think it's cool.
***
They looked like thin trees with huge, bulbous tops. But even this far out, the IR reading told a different story. Nothing on Earth burned that cold. Or at least...nothing from Earth.
"New targets coming up on the HUD!" Commander Tannhauser called out through the internal coms, tagging each entity as it emerged from behind a wilted grey forest. The longer she stared, the more detail she could pick out. Fifty feet tall, stalking on three great spindly legs that stabbed its blade-like feet into the ground with every step. Its main body, vaguely ovoid with all manner of semi-organic protrusions, bobbed with its motion and made getting a proper lock on its centre of mass difficult. Hell, in the initial few weeks of the invasion, humans could barely hit the damn things they were so mobile.
But the crew of the Thunderchild had had practice since then.
"I see em!" called out Ember, and steered the torso of their MK-44 Mobile Battle Suit to bring their weapons to bear. The hum of the pair of arm-mounted magrails filled the compartment, along with the additional heat from the tokamak reactor as it strained to charge several hundreds teslas worth of magnetic induction.
"Good. Load hypersonics and get ready to fire. Poppy, bring us closer. They're not getting away this time."
"Alright, alright," came a voice from deeper within the war machine's body, and the bipedal form lurched into motion. Stabilizing gyros came online a fraction of a second later, keeping aim level despite the jostle of a mech in motion.
This deep in country, the red weeds the invaders planted warred with the native Terran life, curling like clutching fingers around the abandoned signs of human habitation. Tannhauser couldn't remember the last time she'd seen a pasture unmarked by that morose scarlet, save for the carefully tended gardens and fields around citadel cities.
They crossed one of the old highways, gargantuan metal feet crushing cars that went for tens of thousands of dollars pre-invasion without a second thought. Many had doors left open, either from a panicked flight or from scavvers rifling through abandoned belongings. One of the rusting vehicles crunched underfoot bubbled up in protest as its lithium core hit air, igniting in the process.
"Shit!" Tannhauser saw the IR feed light up, swapping cameras to the rear view. "Be careful around those old electric ones, they light up like a fucking flare!"
In the distance, the trio of alien forms turned. Just as their absence of heat marked them to the humans, the explosion of thrown off heat marked the harsher, primitive technology of Earth.
"Here they come!" Ember called, relish in her voice. "First one on the left, range 4700 metres, loading mach rounds...firing!"
Two depleted uranium slugs in ferrous jackets accelerated to several times the speed of sound at the exact same moment, rocking the mech's torso back. In less than a second, they reached their target, punching through the semi-organic armour that the alien machines used and exiting out the back, ending up Newton only knew where somewhere down range. The machine bled a darker red fluid than human blood, seizing in fits as it struggled to remain standing. The air rippled around the remaining pair of machines, and their impossible protective shields came online. Their next shots wouldn't be so lucky.
"Buckyshot next," Tannhauser called, marking the next closest target as the priority.
"I know, I know, loading sandbag," Ember said.
"Less lip on coms, more loading," the Commander retorted. She heard muffled grumbling from the machine's gunner, but the indicator for loaded rounds flashed on both magrails. "Poppy, closer still."
"Ooh, can I do the thing? I think I can do the thing," the driver asked, increasing speed and bringing the mech up to a lope.
"Negative," Tannhauser said, "Keep procedures textbook. I don't-" The explanation died on her lips when she realized that it was too late. With the weight behind the Thunderchild in motion, there'd be nothing but a catastrophic fall if they stopped now. She gritted her teeth. The left arm ammo indicator changed back to a supersonic penetrator, and her fingers dug into her chair's armrest.
The operational tripods responded with lances of nova hot light, a mix of plasma and laser that had melted the original defenders of Earth when they had first fought. The increased speed prevented the aliens from getting a solid shot off, but still, the ablative armour on the mech's hull sizzled and sloughed off. The heat inside only increased, sending sweat down Tannhauser's brow and matting her short cut red hair to her brow. Though the temp was rising in the cockpit, inside she was fuming even hotter. Another goddamn breakdown in discipline.
"The thing" took shape as the driver brought the mech up to max speed.
"Ready Ember?" Poppy asked.
"Do it," the gunner replied.
Now within a kilometre, knife fighting range in their line of work, Poppy hopped the mech slightly, jamming its feet into the cracking asphalt on the landing. The sheer momentum kept them in motion, but slowing them enough for the first shot. The mech's right magarm fired, or rather magnetically accelerated, a densely packed projectile in a magnetic sabot. Microseconds after launching, the package exploded, sending a mist of tiny carbon spheres at an absurdly high speed. The haze of the protective heatshield could handle single tank shells and missiles, but several trillion molecule sized carbon fullerenes at once overloaded its capacity.
Back in the mech, the momentum from the buckyshot round caused the torso spin on its axis like a carousel. All three women were caught by their harnesses as the gigantic machine spun 360 degrees. By the time the left arm was lined up with the target once more, a hole had formed in the overloaded protective field.
Ember cackled. "Bullseye."
The second round was another DU penetrator. It sliced through the first alien machine, completely coring the half-alive tripod in a spray of alien goo and pulsing hardware. The round continued on its course, hitting the force field on the third and final tripod. It melted under the heat of the shield, but the mix of flying debris from its sibling, the scattered fullerenes that had blown right by the second machine, and the sheer proximity of the magnetically accelerated projectile managed to slip enough molten uranium through to shower its hull. It howled in protest before limping away, retreating deeper into alien controlled territory.
"Now that," Poppy giggled into the coms, "Is a new one for the textbook."
Her and Ember whooped, much to Tannhauser's chagrin. She was about to chime in with a proper reprimand, when her attention snapped to further motion from the damaged third tripod. At first she thought it was getting closer, but the legs themselves weren't moving. The body of the strange machine was expanding outward, atmospheric seals popping from the strain.
"Black smoke!" the Commander called, and hit the emergency lockdown button at the centre of her console. All the seals pulling in air from the outside slammed shut as if the metal colossus was holding its breath. Air recyclers kicked in, filling the cabin with the tang of ozone. Just in time, as the final tripod erupted in a cloud of dense fog. Earth plantlife that touched it wilted instantly, while the ever present red weeds seemed to perk up in its toxic presence. The cloud surrounded them and the surrounding area, coating it in the same poisonous miasma.
"Getting us out of here," Poppy said, turning around and stomping back to base. She got half way through the cloud before the emergency heat sinks kicked in.
"Stop! We're burning up!" Tannhauser called. The internal cooling system keeping the machine in operation couldn't function without air vents. Poppy ground the Thunderchild to a halt, leaving it standing like a lighthouse in a black sea. Even above the cloud, the aerosol diffusion of alien toxins would mean death for them all should they crack open a hatch. They'd have to wait until the mech cooled down, or for the fog to dissipate.
They worked in silence to power down all nonessentials, long hours of drill stepping in for a lack of crew harmony. Reduced power draw would keep them from cooking, but the mech would be exposed and vulnerable until then. The three women managed to keep their ire nonverbal until the power graph dropped down to minimum. Then-
"What the hell were you too thinking?!" Tannhauser seethed. Poppy crawled up from the driver alcove, popping the com bead out of her ear and letting the bud dangle down the neckline of her grey tank top. Mech jocks had a much looser dress code in comparison to other branches of the military, but her bright blue hair that tickled her shoulders was pushing it. She was also the tallest one out of the trio, standing a statuesque 5'4 in combat boots.