"The Beast" is just ridiculous

Well... Some wall climbing and some shotgun blasts to the chest.

I understand what you're saying regarding expectations, but a film soundn't require supplementary materials for the audience to orientate themselves in it's universe.
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It doesn't, the film 100% works as a stand alone, If The end shot featuring Willis wasn't there, They film still completely work as a supernatural Thriller

The film ends With The screen black and The Title "SPIlt"....that absolutely could have been the end of the film and The film works perfectly, You dont Need The After credit scene to make the movie work, It was added by choice not by Necessity.

Everything should be set up in the film itself, and I shouldn't need to turn to the trailer, or another movie, to explain what's happening.

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Again you dont. The Film works on its own as a Supernatural Thriller, If you dont understand what happened in the Movie thats on You, The movie was simply, It works both as a stand alone and as a part of a bigger universe.

You dont Have or Need to watch Unbreakable, You can completely understand and enjoy the movie as a stand alone, You can completely leave the theater having just watched A "Supernatural thriller about Split Personalities...

If you really enjoyed it, Then Thats when it gets even better, If you loved the movie, Then thats when The Post credit Scene Adds even more to the movie by connecting it to Unbreakable

Its your choice, You can completely view the movie as a simply stand alone movie, The story 100% makes sense as A supernatural thriller...

If you've Seen Unbreakable, You can then view the movie in a different light

either way the film works

All they did in terms of a set up was to have the personalities say "The Beast is coming". I didn't see any hints that there are going to be supernatural elements in Split untill The Beast showed up and started walking on walls and all that.

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In The trailer They are Painfully clear that the film is going to be Supernatural and The Beast itself is going to be Supernatural...

in The Trailers We literally see Snippets of McAvoys Body Transforming in A clearly unnatural way, We hear His Bones Cracking and Popping which indicates his body is transforming...We get A Snippet shot Of McAvoy in The Hallaway Climbing On top Of The Ceiling in a way that clearly looks superhuman or completely Unhuman.

I literally do not see how anyone could watch the trailers for this movie and come in with expectation that The Beast Isn't going to be Supernatural.

again I think This is more of a YOU problem than anything else....You clearly Misunderstand The Trailers for this movie.

You went in expecting something that clearly wasn't sold or marketed, This movie was Marketed Perfectly, The Hints of Supernatural wereThere, You just missed them and as a result went into the movie with the wrong expectations

And correct me if I'm wrong, but I didn't see it being marketed as being a part of the Unbreakable universe.

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Your right, there was zero marketing suggesting it had anything to do with Unbreakable....and the reason why was because It didn't need to be...

The Film can Stand on Its Own...You dont need to see Unbreakable to enjoy and Understand this movie.

Basically, the supernatural/superhero elements should have been introduced in the movie earlier, if we were supposed to be seeing it as a stand alone

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Ok now I'm questioning if you actually even seen the movie?

either you haven't seen the movie or you just didn't pay attention.

The Supernatural Element was introduced very early(I think In the first 15 Mins) and was repeatedly talked about and mentioned as A Subplot.

That was the Purpose of The Doctor's role...after Kevin's first meeting with the Doctor(again In The first 15 mins, right after he kidnaps the 3 girls) Kevin Leaves, The Doctor goes over to her neighbors and is watching TV and Then first Mentions That "Maybe People With Split personalities are The Ultimate human form or something like that, she mentions that maybe they have been able to tap in to The Brains Full Potential, and for the rest of the movie she repeats it even giving a Lecture, talking about how powerful Split personalities could be and how there could be no limits.

I'm sorry but you missed all these Hints+Clues, Literally her entire character and Ark was her introducing and Explaining The Supernatural elements of Kevin So Later on in the movie "The Beast" being Supernatural didn't just come out of nowhere.

lol somehow You entirely missed A Huge Subplot in the movie, You missed An Entire character setting up The Supernatural elements so when The Beast does turn out Supernatural, It actually makes sense and was sets up instead of just coming out of nowhere

if we were supposed to be seeing it as a stand alone. Or it should have been marketed as a part of the Unbreakable universe, so that people didn't get confused, or go in with the wrong expectations.

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again this is a YOU Problem....Most everyone else went in with the correct expecations