The only stage I was able to try out, some sort of underground facility, was packed with enemies, but pretty straightforward. (wccftech.com)
These come from beautifully designed brochures for a Top Secret underground facility to a chair. (thezombiechimp.com)
This is followed by a high - tech underground facility with severely limited movement, as not only confines you to a single line but also prohibits jumping with a row of spikes on the low ceiling. (hardcoregaming101.net)