If you like horror films made for the family, this is an A+.
If you prefer a linear narrative focused around a strict set of rules, this movie fails in every aspect.
Characters are constantly swapping between brilliant and idiotic, by which I mean the entire plot is centered around every single character making illogical and irresponsible decisions (yet, sometimes questionably informed ones) that have little-to-no logic, and next-to-no consequence. They hardly ever face repercussions - up until the last 30 minutes - yet most of the time you don't understand why they got away with their actions.
This movie tries to make the viewer feel smart because it presents itself as if the audience is always "in" on the rules, but it's constantly flopping back and forth between "this follows everything I've seen" and "if this was dangerous before, why are they barely escaping danger this time?" It removes all of the tension, and every moment of release feels undeserved.
Overall, this movie is comparable to an average Netflix-produced film that relies more on soul and familial values rather than a cohesive narrative that confronts the dichotomy between soft and hard magic.
I'll give it up, the first 10 minutes are fantastic. They set the tone, and actually make you understand the rules and feel their struggle. But if you want to see a film about unrealistic characters in a confused world that relies on Deus ex Machina rather than clever writing, this is the film for you.
In general, I felt all of the tension was a result of all the main characters' lack of reasoning and planning rather than the innate threat the antagonists presented. There are far better films that make you think about why the antagonists do what they do, and I found myself - most of the time - struggling to find a reason to care about the main characters and the reasoning behind their actions.
It's an incredibly original idea, only to result in wasted potential because they couldn't take a few extra minutes to think about the development of the characters and the world they live in, i.e. much of the character development is implied, rather than explicitly presented and expounded upon.
It's unfortunate to engage in a film with some of the best acting in recent films of the similar horror genre, only to be undercut by lazy and irreverent writing.
Hopefully the sequel does better.