The Earth Defense Force is an organization in Serious Sam 3: BFE.
The Earth Defense Force appears to be the main military force fighting Mental's advance towards Earth. Based on NETRISCA descriptions of humans fighting Mental's forces, the EDF has several military spaceships and enough equipment to protect holdings on other planets. The EDF also seems to have the ability to manufacture their own ammo, as the Ammo Crates mention an organization called “EDF Corporation”.
When Mental invaded Earth, the EDF rallied to defend their planet. Despite Mental's superior technology and magic, his army took many casualties, as the NETRISCA description for the Hatchling Arachnoid implies that Mental had to send off his troops younger and younger with increasingly inferior equipment to replenish his losses. However, Mental's numbers ultimately prove to be too much for the EDF to handle, and by the time of Serious Sam 3 most of the EDF has been destroyed.
In Serious Sam 3: BFE, the Earth Defense Force is depicted is a small force, with only one headquarters remaining. The fact that Cairo is completely abandoned suggests that the EDF is no longer capable of fighting Mental directly, and instead does more covert operations against him, such as inserting small groups into Cairo to retrieve data for a new plan.
Instead of fighting Mental directly, the Earth Defense Force is creating a plan to kill Mental in the past by using an ancient Sirian artifact called the Time-Lock thus changing the future. This will let the EDF insert a group of soldiers know as Charlie Team into the past, travel to Sirius and assassinate Mental while he is dealing with other matters.
The Earth Defense Force's headquarters, along with everybody in it, is wiped out near the end of the game that includes the Charlie Team via a sneak attack on their headquarters by Mental. The destruction of their last headquarters and the Charlie Team signals the end of the EDF and destroying humanity's last hope, which allows Mental to safely finish off Earth by tossing Earth's moon at it causing it to destroy the EDF's homeworld.
Despite Mental's best efforts to destroy the humanity, EDF and planet Earth, Private Sam Stone is able to successfully escape from the Earth's inevitable destruction via the timelock, making him the last man on Earth and humanity's last hope.
- SOP38 Pistol
- 12 Gauge Pump-Action Shotgun
- M29 Infantry Assault Rifle
- XPML21 Rocket Launcher
- XM-214-A Minigun
- RAPTOR Sniper Rifle
- AS-24 Devastator
- C-4 Demolition Charge
- Ammo Crate
- ASU 7 Automated Sentry Unit