Forced Termination

Forced Termination (強制終了) is unique amongst the other phenomenons in the sense that it is not initiated by the Heartseeds, but automatically activates under certain conditions. This phenomenon appears during the Nise Random and  Asu Random I arcs.

Description
Forced Termination automatically activates in response to two or more people experiencing a paradox as a result of a phenomenon, for example, if two or more people observe the same Illusion Projection at the same time. The ensuing paradox will cause the observers to have their memories reset to before ever encountering Heartseed. Heartseed apparently has some control over this phenomenon and was able to return the memories of Taichi and Yui, but not Oosawa.