
Rex Soft (雷克斯軟體工作室) was a company that developed a number of pirate originals for the Famicom during the mid-1990s. These games share a sound engine and fonts (the latter taken from Borland BGI) with most of NTDEC/Asder's original games, so were probably created by at least some of the same development team, but it is unknown whether they were produced under Asder.
Rex Soft has been active in the gaming industry from 1995 to 1997, with 3 titles tracked on PlayPile. Their catalog primarily spans Hack and slash/Beat 'em up, Platform, Fighting, with additional titles in other genres. Their games are available on Family Computer.