Our game group has played many sessions of Palladium Books Rifts Chaos Earth over the years.
We have played every day people on the fateful day of the apocalypse.
We played another set of every day soldiers / scientists near the VLA and fought demons and the endless hordes of the walking dead (long before zombies officially came to CE).
We also played as members of the NEMA Mid West Command, Denver CO the characters traveled across Colorado, the mid-west states and ultimately discovered tech based dimensional portals located in NORAD, Lone Star and other locations. Using one of these portals they ended up in outer space and eventually on Mars before returning to Earth a year plus later. Returning to Earth they found the Mid West Command of NEMA gone / destroyed.