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// Sightless Through The Fire 
// Story: Book 1 - The Behemoth came to Canterlot 
// by Equimorto 
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Stella dodged to the side, looking at the scorch mark the spell left on the ground as she rolled in the air. She scanned the area above for traces of Trixie, but couldn't see her. Another spell came from behind her and she avoided that too by moving to the side. Then another, and that time, after she'd avoided it already, it bounced in the air and headed towards her once again. Stella caught sight of it in time and neutralised it with a wave of her horn.
She was tense, looking around both for signs of the pony and to spot spells she might cast while her brain worked to figure out how it was possible that Trixie was seeing her. But it wasn't. She knew that with certainty. Therefore, Trixie wasn't seeing her. She wasn't hearing her either. She was detecting her position, in some way, and that of her spells as well, but it wasn't anything Stella hadn't already covered with her coil. If it had been, if Twilight or maybe even Trixie herself had found a way to ignore it, at the least the other alicorns would have remained there to fight after being instructed on it.
It had to be something else, something only one pony could benefit from at once, maybe only Trixie specifically. Stella was already getting ideas for what it could be exactly, and all she needed was a chance to test out her guess.
Unfortunately for her, Trixie was doing her best to leave her without an opening. She had little time to think and even less to act in the face of the unicorn's repeated blasts, always coming out of nowhere and always aimed at her position. Stella was growing tired of it, and though at that point even she couldn't deny the fight had tired her she still chose to go for the brutally effective if wasteful solution.
First she put up a shield, which Trixie's spells began to uselessly crash against. Then her horn glew brighter and her shield started to glow as well. A moment later she released her magic, like releasing a breath. Magic surged rapidly from the ground in a large area around her, like a giant lightning bolt from the earth to the sky. It was just a flash, if a tremendously powerful explosion that blew dust and sand around in a shockwave and echoed around for almost the whole desert, but it was enough for what she needed it to do.
Trixie had to protect herself, and her shield gave away her position. Stella felt a sting of wrath as she realised the unicorn had gone invisible to her, and she let the emotion crystallise into a long sharp chunk of condensed magic she charged with towards Trixie's location. She moved fast, and though the other might have seen her she still didn't have the time to move, and Stella's artificial stalactite impaled Trixie's shield and shattered it in a shower of red.