"As she did, she put two of the acorns, which were glowing, into her cheeks." "which were glowing" is kind of clunky, though I understand what you're getting at. Consider making it more concise, like "now glowing".

"She kept a tight hold on the knife as she was run down by bullets, tearing her to shreds." This could have a huge amount of shock power, but the quick switch between active and passive voice is jarring. I'd keep it all in active voice, and my personal preference would be to join her action and the bullet's action by an em dash--but how you connect these important actions is your chocie.

"Sonia scoffed as she glanced at the two before they disappeared, and her eyes then moved down to squint at Makoto,"
These actions can be more concise with fewer subordinating conjunctions. Although subordinating conjunctions can help clarify, often, what they express is deducible by the reader, who wants to hear all about the actions and may get distracted by the context he or she already assumed.

"who shimmered slightly as if emanating a heat haze." I like the comparison here, but I think because you already have a verb you can create variety by using a noun with adjectives as the simile. "who shimmered slightly like the... [heat haze]." Professional writers seem to do that a lot--for good reason.

"She threw a knife with a red gem at the hilt of it." This description can be made way more concise. When an action is important, try and get in all descriptions as concise as possible, or if you have many devote more time to describing the knife. Or throw out unnecessary descriptions.

"She threw a knife with a red gem at the hilt of it. The gem glowed once Sonia finished her incantation, and suddenly knives replicated at an alarming rate from the original knife." Once you make the knife's description more concise, you can possibly combine all these actions into a concise (I know I use that word a lot), action-packed sentence or two. For example,
"Words still spilling from her mouth, Sonia hurled a ruby-hilted knife and finished her incantation. The gem glowed—and the knife split and split again, circumscribing Makoto with a bladed ring. In the blink of an eye, they launched."
This paragraph says everything the previous one did, but it hurls each action at the reader like Sonia's knives, yanking them into the action and then shoving them into the fray.

i have to wash the dishes now so just
remember these principles I guess