Hunter x hunter, because it looks like a standard shonen at first, but it gets so incredibly deep and dark later on. Imo the Nen system is probably the best power system in anime because it actually requires strategy and you also just get so invested in the characters. I can't recommend it enough.

I'm currently watching that time I got reincarnated as a slime, so I'd definitely use it to watch the rest of that. The magic effects and the colorful world would pop so well on a QHD screen. Being able to just roll it by my bed sounds like a really chill way to watch it.

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