Fluttershy spread her wings and pushed herself back, while Shining and Cadence ran forward towards Stella. The alicorn, still in a state of shock as her body fought back the parasites spreading through her, only managed to hold up a shield and protect herself from their combined spells. She was pushed backwards, and rocks and lightning crashed against her barrier as the remaining ponies joined in. Things didn't last like that for long.
Stella grit her teeth as the shifting multicoloured patches over her body began to retreat, her horn ablaze as her magic both shielded her against a combined helix-shaped blast from Shining and Cadence and coursed through her being, forcefully ridding herself of the disease Fluttershy had share with her. A few seconds later, while her shield was starting to crack, the last traces of wrong colours disappeared fully, surrounded by sizzling sparks. Stella's spell broke, and she teleported. The twin beam of magic left a glass trail through the sand as it passed where she'd stood and beyond, before being undone. Everyone stood alert, carefully watching for where she could be.
Fluttershy, who'd been hovering above the ground some distance away, felt her body seize up, like electricity running through her. She couldn't even scream, but the others noticed her falling to the ground, limbs stiff. Before she reached it, she ended up encased in a translucent white sphere, halting her fall. A moment later she was free to move again, but wholly trapped within the magical bubble.
Rainbow understood what was happening, and made an effort to kick a lighting bolt off the cloud she'd kept there aiming at the space at Fluttershy's side, behind her. She didn't hit anything, but evidently she hadn't had the wrong idea. She felt herself choke as Stella came for her next, then there was a flash of light and she lost consciousness. When she awoke a moment later she was trapped as Fluttershy was.
Rarity and Pinkie stood with their backs to each other, eyes darting around frantically in search of any signs of the mare. The first felt herself yanked forward and pushed against the ground, hard enough for her teeth to draw blood from her lips as her mouth tasted sand, then a pressure against her horn that blocked off her magic as she was encased in another glowing white bubble. Pinkie Pie was flung skywards, and slowly came down inside a sphere of her own.
Shining and Cadence both fired tentative shots near the others, towards places they could guess Stella might be, but never hit her. They stood side by side, waiting for her to come. Then in an attempt to buy Twilight more time, they teleported away in different directions, each putting a shield around themself, and began to repeatedly move that way.
Shining was caught right after one of those teleportations. A sudden flare of magic and his shield shattered, knocking him unconscious. Then Stella revealed herself to Cadence, picking up Twilight's crown.