The effect is made by Sajad Alavi.
FX Artist Sajad Alavi presented an awesome smoke portal created using Houdini.
The creator also kindly provided the files for the project, which you can get from Gumroad for $25. There is a HIP file as well, which contains techniques you can use in other projects, according to Alavi.
You can find more great works on the artist's ArtStation, including other smoke, particle, and portal effects.