Diamond's Dimensional Quests: Your Turn To Die

Diamond Dewdrops is feeling better than ever about herself. She's had a rough past of battling depression and her family history, and her dimension-hopping detective work puts her through a good deal of trauma, but she's clung on and rose above it all. She has great friends, a loving family, and high grades that have colleges from far and wide looking at her. While her goofy and often misguided efforts often make her a misfit and land her in trouble, she takes comfort in knowing the past is far behind her and all that's important is her actions in the present.
But she's wrong.
Unbeknownst to Diamond, a single overlooked error in her past led to a darkness blooming, which attacked and kidnapped her that very same night. When she wakes up and finds herself somewhere she's never been with her power neutralized, it becomes clear her experience was far from a one-off, and that people across dimensions have been kidnapped and trapped alongside her. From out of nowhere, an AI appears on a screen above everyone's heads, announcing why they were all brought there: they were brought here to play a kind of game of fate, where they would be forced to choose a different person to die every day and watch their death play out on the screen above. The AI also announces that somebody here was a traitor who brought them there in the first place. If they don't obey, everyone but the traitor will be killed. With more pressure on her than ever before and her distrust putting her hope of escape and rescue to the test, it's up to Diamond and a few familiar faces to find the culprit in the dimension hopper's most dangerous mission yet, all while she learns the biggest lesson of all:
Some secrets do more harm than good if sealed away from our loved ones.