Fantasy setting, not on Earth. Main character (let's call him Boy) is getting his first ever tarot reading from his badass witch of a teacher before she begins showing him how to do his own readings. Unfortunately, Boy is a latent balled-up vortex of power, destruction and death just waiting to spring into motion, and the cards know it. He's just 'killed' one deck by pulling impossible numbers of duplicates of the Tower card from it, and his teacher has brought out a more powerful deck and has asked him to pull X number of cards this time and turn them over one by one.
My question to the experts is, what sort of reading would ring some serious alarm bells about the subject? Boy is interested, open-minded and completely ignorant of anything to do with Tarot (and largely clueless about what he is and what he's capable of) while his teacher tends to think of tarot as mixed parts minor magic and psychology/manipulation, and has a reputation for being fairly unshakeable. Ideally I really want to shake her, so the nastier and more unambiguous the reading the better (if the Tower can come out again first I'd be really happy, but am willing to sacrifice it for anything worse that anyone can cook up?)
I've googled for the meanings of the major and minor arcana (hence why I'm set on the Tower being a big theme whenever he touches a deck, though I know it also has positive interpretations which I'd like to negate as much as possible) but I haven't found much helpful information on specific combinations of cards that would set off a serious warning in the reader's mind -- most people online are good people who seem to try and focus on possible positive meanings of 'bad' combinations instead of what else they could mean, which makes generic websites less helpful when I'm specifically looking for no-doubt-about-it badness...!)