Delta Green: The Millennium

One of the most infamous works for Delta Green, the sourcebook Countdown, adapted and edited and rearranged for Delta Green: The Role-Playing Game.
At 336 pages long, The Millennium includes PISCES, GRU SV-8, The Skoptsi, Outlook Group, Phenomen-X, Tiger Transit, the D-Stacks, the Keepers of the Faith, the King in Yellow, and the Emerson Files. All are as Delta Green encountered them 20 years ago, in the pivotal days when one millennium bled over to the next.