The coma, is the “Inception for Dummies”.
The movie is an average attempt on what could have been a masterpiece. Even though the movie is of Russian origin, it is seldom visible on screen. Everyone who is in coma is trapped in a different world from where they need to find a way out, without getting killed. Everyone in this world has a unique ability and our hero has the power to materialize any structure just by thinking about it. This concept alone could have been made into an amazing cinematic experience, but the makers fall short.
The final reveal is rather exhausting and you are left scratching your head. The cinematography and VFX are good in some places and simply fall flat sometimes. It looks like the makers lost interest in the movie midway.
Overall, it better to avoid getting into the coma (pun intended), if the world of coma is going to be who it is shown in the movie.