Take up arms as the newest recruits to the XCOM project. An alternative retelling of the events of the first contact war set instead in 1991, as your group participates in the world funded XCOM project as a secondary base newly created somewhere in the middle of Arizona.

-GURPS Basic, High Tech, and Bits of Ultra Tech (may need to adjust things here and there for balance/getting the XCOM feel of course)

-100 Points To Start, 50 Points Disadvantages

-Become Gene-Modified Super Soldiers, Half Mechanized Monsters, or Delve into the Powers of the Mind through Psionics.