Earth Defense Force 2017 Portable is a third-person shooter developed by Sandlot and released in 2012 for PlayStation Vita. A remastered version of Earth Defense Force 2017, it tasks players with battling waves of giant insects and other enemies across its campaign levels. The portable release adds seven new stages to the original game's content and introduces Pale Wing as a playable character alongside the standard trooper. Pale Wing is equipped with a jet pack that enables aerial movement over buildings, opening up a different style of combat compared to ground-based play. The Vita version also supports online cooperative multiplayer for up to four players, allowing groups to work through the game's missions together. The addition of new levels and an extra playable character distinguish it from the original release.
In 2013, radio waves from deep space are received by scientists, revealing the existence of extraterrestrial life. Two years later, the Earth Defense Force, a unified multinational military organization, is established in case the aliens are hostile. In 2017, first contact is made when hundreds of unidentified flying objects suddenly arrive and hover over major cities across the globe, led by a massive mothership positioned over Tokyo. As the EDF is mobilized, giant acid-spitting insects resembling ants begin assaulting many civilians. The main character is an unnamed Captain in Storm 1, a Japanese unit regarded as the EDF's best. An air assault by the EDF is attempted on the mothership, but the plan is thwarted by alien UFO gunships. This operation is deemed a failure, resulting in the surviving EDF forces abandoning the cities to begin a guerrilla campaign in rural areas.
