Possession is currently under development (earlier in development, it was called Possession 2 but the name has been changed to simply Possession). It will have over a hundred more creatures than the original, as well as special levels, level features, and numerous improvements in the game mechanics and interface improvements (not the least of which are graphics).
I’m posting occasional dev blogs as I develop it.
It will be available for Mac, Windows and Linux, planned for a late 2017 release.
There’s a preview build available, which features two complete levels from the final game:
The Steam page for the game is live, so you can wishlist it or follow to see when it’s released:
Here are some (admittedly out of date) in-progress screenshots (click to expand):