2 1/2 of the makers of the L4D(2) mod Dead Before Dawn went solo and created THE CORE.

Umbre says

6/10 -

Some fresh concepts, but some new puzzle elements were awkwardly presented and I was unaware of how they were to be used. Voice acting was a bit cheesy. Some lines felt out of place, and I wasn't sure why certain things were being said. Level design was good for the most part, but some chambers felt lacking in detail, awkwardly built, and there were lots of mis-aligned textures. Overall, 6/10 for effort and new ideas, but quality is a bit lower than expected.