There are plenty of people calling for violence right now. Find a few disaffected male 20-somethings already leaning towards those ideas, groom them to see if any will go further, coordinate a plan with them, and you can have an “unscripted” but predictable attack. I don’t think that part is unbelievable, although I don’t personally have a strong feeling on if this particular attack was staged.

My dad got an art degree by taking one course per semester for years. He loved it. Got his degree last year. Retires this year.

Baking cookies from scratch is easy and cheap. Here’s NASA’s recipe: https://spaceplace.nasa.gov/sunspot-cookies/en/