The Transformers: Call of the Future

The game's story, titled The Transformers: Call of the Future, takes its cue from the original cartoon, even specifically referring to the events of several episodes. It is (presumably) set in 2003, the year it was released, but, via time travel, also features characters from an alternate future which branched off from cartoon continuity in late 2010 (after the events of "Webworld", but before "The Return of Optimus Prime, Part 1"). It does not seem to be officially considered part of the Japanese Generation 1 cartoon continuity, however; it features several anachronistic appearances by characters who are not time-travelling (the Headmasters, for instance, are shown to be working with their respective factions, when they will not leave their homeworld to do so until 2011), and its events were not included in the painfully comprehensive 2007 timeline.