Here is an overview of Earth Defense Force 5, via its Steam page:
Stand and fight for humanity.
This arcade shooter takes place in the year 2022, as the Earth Defense Force fends off an all-out attack by unknown life forms. Become an Earth Defense Force soldier, battle against endless hordes of immense enemies, and restore peace to the earth.
Make way for the series’ first humanoid aliens.
Just what is this intelligent, extraterrestrial civilization that has attacked our own, known only as the Primers? Matching their intelligence, they bring the series’ first humanoid alien foes. Battling against these intelligent foes will bring you to the depths of yet-unknown despair, and the heights of joy.
Face the enemy with wisdom and courage!
The most jam-packed entry yet, with online co-op play!
This entry has more missions and weapons than any before it. On top of that, all missions support online co-op of up to four players, as well as local split-screen. Control the four classes and play with Earth Defense Force soldiers all over the world.
This is no training exercise.
This is the living nightmare we’d all feared.
It all started in Japan, 2022. An immense fleet of starships laid siege to an Earth Defense Force base located in the rough city outskirts in the Kanto region.
This was an enemy humanity had never encountered, the Primers. Even worse, enormous insects attack the Earth Defense Force base built even further underground. The Earth Defense Force fights back.
Even More Realistic Battles
Armor will peel off where you shoot enemies, and their fluids will spill out onto buildings and floors, making you feel like you’re truly on the Earth Defense Force’s battlefield.
Four Earth Defense Force Classes Powered-Up Like Never Before
As the player, take on missions with one of four classes. Finish missions to unlock new ones and advance the story. You can switch classes before missions as many times as you’d like.