Players can transform the terrain to obtain energy, use as offensive tool or improve defenses while having to deal with hostile geological processes and entities known as 'Scourge'

Taking place in the Chains of Worlds, players assume the role of Legates, commanders of frames, overseeing base development and leading strategic battles. As the narrative unfolds, players embody different Legates from various factions, providing multiple perspectives on unfolding events.

Centuries after the Exodus, new coalitions emerge, challenging the ideals of the spirits. The Return coalition, led by the Committee of Truth, seeks to return to Earth from the root worlds, rejecting the spirits' dogma. Similarly, the Spongean Empire advocates for enhanced humans conquering the Psychosphere rather than marching towards promised utopias.

Players undertake missions for different factions, shaping the narrative of the Psychosphere's history over centuries. This extensive timeline makes it challenging to introduce human characters, resulting in a unique storytelling approach.

Perimeter offers a rich and complex narrative, although some elements were omitted from the international version of the game, leading to community efforts to translate and clarify the storyline. Dive into the immersive world of Perimeter and command your forces in this strategic journey across the Chains of Worlds!