Due to lack of available information, it is unknown whether or not the series was introduced in 1992 or 1993. It is speculated to be 1992, although the series did not make an appearance in the 1992 Kenner Guide, only to be seen in the 1993 catalog. This could hint at a late 1992 release, as the 1992 Kenner Guide had been released in very early 1992.
Originally a blaster named the Harpoon Crossbow was planned to be released after the Hydro Bazooka. However, due to bad popularity of the line, it was patented, but never released. It was supposed to work as a projecting bow similar to the Nerf ActionCrossbow and had a special type of arrow that had water stored in the tip. Strangely, the ammunition would later be released in its own refill pack without the blaster.