Dead Cyborg can be downloaded from the site (I recommend version 002 as it supports mouse look instead of just the arrow keys). To get it running you simply extract it and run one of the four bash scripts provided depending on which suits your needs. The game ran flawlessly for me on both Linux Mint and Arch (there is a package available in the AUR).
You start the game waking up in some sort of cryogenic freezer, not knowing who you are or how you got there. As you advance you read messages left behind by your colleagues who had ventured out of their capsules some time earlier, before their deaths at various stages along the way due to radiation posioning.