What started as a mixed bag of dialogue, editing, and bizarre camera techniques turned into a very fresh and creative slasher horror that knew how to use the build-up, the excess of violence, and a pretty cool plot twist.
The film could've been shortened, especially in its first act but the rest will compensate for the iffy beginning. It's not the strongest on characters compared to other Wan films. It's mainly a concept movie with characters inhabiting its world.
The jump scares did not work at all. The fear comes from shocking reveals and gore in contrast to atmosphere or jump scares (which were very few and not well-made). But there are cool CGI scenes that will creep you out and the film knows how to balance practical and digital effects. There was one shot which was supposed to be scary but ended up being funny at the end which was sad because at this point the movie had become so intense. The film had a fresh killer that was shocking and bonkers that is on par with Michael Myers.
The musical score had two personalities: either cliche horror music or crazy metal vibes and it was overused at many times that it became annoying. Malignant provides some really cool experimentation with the camera that I found to be innovative albeit overkill at some points - though it was essential. I disliked some of the exposition and the flashbacks which were unnecessary sometimes because when they were heavily used, you would've been able to piece out the entire clues and evidence and understand what's going on. I was able to predict most of it halfway through but nevertheless, the full reveal is shocking (and a pleasure if you're a horror buff). One thing I totally disliked is how the film resolves itself at the end which was an eye-roll moment.
The film had an interesting subtext that could've been given more room to be fleshed out and would've raised the importance of the film.
I think it's one of those horror films that are best enjoyed with a group of friends reacting to everything on screen because there are a few shocking moments that will remind you why you love the horror genre.