Hey Marius, awesome piece as always. This piece is catchy in a way since I don't know what to expect next. I love ambient music, and I think you have done a pretty good job on this. When the choir first came in, I swore I had heard that melody before, just forgot where from. Gregorian chants seem interesting, may get some to listen to. Mind telling us which vsts you made this with? Especially those ambient sounds.
Next, this piece does feel other-worldly, mainly because of the choirs, but I don't think it sounds tribal. The choir also added a sense of "creepiness" to the piece, and I love creepy music.
To sum it all up, this is a really good piece(as usual) by you.