The mid-day sun cast it's relentless gaze upon the desolate landscape. The Savannah spread out in waves of brown, orange, and vermilion with mostly just grass as far as the eye could see. There were a few pockets of rock outcroppings or thin copses of trees, but little else. Overhead a few thin clouds drifted through the azure sky. The Battlelord didn't mind the heat, reaching down to lightly brush her fingertips along the thick clumps of turu-grass. Straightening back up, the Sith strode forward to an area where the turu-grass thinned out, leaving patches of bare sandy ground exposed to the baking sun. The wildness of this place seemed to call to Rasilvenaira, and was a welcome break from the permacrete and durasteel she'd been surrounded by recently.
Dry sand crunched lightly beneath her boots as the Battlelord chose her position in the clearing. She angled herself to have the sun as much at her back as possible, though it was nearly straight over head already. Rasilvenaira was glad she'd worn her usual attire, the thin loose fitting gray shirt and black pants would at least be more comfortable in the grueling heat than heavier robes or armor. They offered less protection against weapons, but this was a risk the Sith was willing to take. Her own weapons hung at her hips, ready and waiting. The Arashi-Kumori, the double-bladed dagger, was on her left hip. Its dark metal blades always thirsty for blood. On her right hip, the finely crafted hilt of her lightsaber rested, like a sleeping serpent waiting to strike.
Taking several slow, steady breaths Rasilvenaira stretched her attention outward beyond herself. As details flickered past her perception each was simply noted and set aside as unimportant. There was the pungent scent of the turu-grass where blades had been bruised or broken by her passing despite her care in doing so, the faint earthy scent of the dry sandy ground beneath her feet, the sound of a light breeze stirring the tips of the grasses, distant calls and cries of various birds or animals. Finally the Sith found what she'd been watching for and her senses focused on the half-Sephi as Shadow approached from behind and slightly to her left.
Clever girl, the Battlelord thought silently as she slowly turned to face the young woman.
Shadow stopped when Rasilvenaira turned to face her. The half-Sephi's golden eyes swept over the other woman, studying her. The Battlemaster gave a curt nod of acknowledgment and rested her right hand on the hilt of the lightsaber hanging at her right hip. The leader of Tacitus Athanasius stood with a certain confidence in her stance that hinted strongly at her abilities and skill, from the slight lift of the chin to the relaxed but ready way she carried herself.
Rasilvenaira offered a small smile. The Sith recognized that fire and confidence, having seen it in herself many times over the years, and she respected it. However, that measure of respect did not mean she'd take it easy on the girl. The Battlelord returned the nod briefly as she unclipped the lightsaber from her belt. The molten silver blade sprang to life with a hiss and a menacing hum. Rasilvenaira spun the saber in a small flourish before lifting the blade in a salute, using her free hand to beckon the younger woman on.
Shadow shifted into a ready stance as she drew and ignited her lightsabers. The blades hummed and whirred as she moved, one crimson and the other white. Staying light on her feet, the half-Sephi closed in on Rasilvenaira, testing the older Sith's defenses.
The Battlelord's dark eyes held a hint of amusement as she noticed the colors of her opponent's blades. Red and white, just like the turu-grass. The idle thought was considered and then brushed aside as she circled to her right, the hilt of her saber held in a loose, ready grip. Like the flexible turu-grass surrounding the clearing, once in motion, the Battlelord would likely stay in motion. Rasilvenaira sprang forward, twisting the silver blade around in a tight upward diagonal arc aimed at Shadow's midsection.
Syntax:
No hyphen in 'midday'. I'm not sure if it was a typo, but it's = it is (much like what's = what is) while its = belonging to it (much like his = belonging to him).
No need to capitalize 'savannah' here. I'll let it pass without a ding because it's capitalized in the venue name, but really it's just a generic savannah on Shili.
Hyphenate 'loose-fitting'
First half is fine. The second sentence, though, is a fragment, since it doesn't have a main verb. There are two easy fixes. You can just merge the two into one sentence by changing the punctuation, or you can add 'was' before 'always hungry'.
Story:
Too many ACC writers barely acknowledge the venue. You, on the other hand, made excellent use of it. Shili isn't a venue with a lot of combat-ready accoutrements, but you worked it into your character's thoughts as well as the description of the area.
However, there are a few things I look for in every opening post in every battle I read. First: why are you there? Second: why is your opponent there? Third: why are you fighting? I got none of that here, so I've got no emotional investment in the story you're telling me. This gets more egregious in the final posts, where Shadow treats the fight as a friendly test of strength but you leave her to be eaten by wildlife.
Realism:
It seems odd to me that a Shadow wouldn't be trying to use Force Cloak while sneaking up on someone. Shadow's not particularly good at it, so I can see how Ras would either be able to hear her via Perception or Sense her, but the way you've written it makes it seem like Shadow is completely visible when Ras turns around.
Continuity:
No errors for obvious reasons.