LSD Jellyfish wrote:An item not being used in a subsequent film isn't the fault of the film it debuted in.
Look at the frequency/homing device that lured Godzilla away from Tokyo and into a volcano, it is never tried again in the Heisei series. The Cadmium missles also worked very well, but Super X2 was missing them. They don't show up till Super X3, 6 films later, where they worked very well again. Anti-Godzilla weapons are meant to be a one film only invention. At least with the ANEB it has the same out as the Oxygen Destroyer, the only scientist able to create the weapon dies taking the secret to their grave.