In the first edition of 2300 A.D. role-playing game (titled Traveller 2300), the alien Kafers invaded one of the human-dominated worlds.

As reviewer Jim Bambra noted, "Invasion is not designed to let any one party of adventures win the war [...] This doesn’t mean that PCs are wasting their time, but that the Kafer threat is so huge that only a concerted effort by the nations of Earth can hope to defeat them.

[2] As part of the updated storyline, GDW published Invasion the same year, a 72-page perfect bound book written by J. Andrew Keith and developed by Lester W. Smith, with interior art by A.C. Farley, Liz Danforth, and Bryan Gibson, and cover art by Steve Venters.

[1] In the May 1989 edition of Dragon (Issue #145), Jim Bambra thought this was an extremely strong work, saying, "Invasion makes for an ideal continuation of the struggle against the Kafers.

He concluded, "Invasion is highly recommended as a model of how to design epic struggles and as a brilliant background to a 2300 AD game campaign.