Interesting concept, but when the conflict happened I was a little worn out by the constant clicking. I played on a PC and the "click-to-type-then-click-to-send" was bothersome.
One feature that would improve the story would be showing Alyssa's texts with fewer clicks. A click should show all her texts until someone intervenes.
Anyways, a hero chatgroup seems like a nice idea. I wish Alyssa's involvement with the group had more weight to it, maybe the group is stuck with her, maybe she knows the secret identity of one of them... not my story, I get it. But It feels Alyssa joined them just because.
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Congrats on finishing your story!