The Gulp Worm was the result of Umbrella experimenting by introducing the
t-Virus into earthworms. They retain many of the garden variety worms characteristics such as sensing vibrations through the soil but instead of using the ability to avoid confrontation, they use it to use as a hunting aid.
They gained a specialised digestive system which had the capacity to hold an entire human body and digest it entirely within a few hours.
Research on the Gulp Worm was halted prematurely when Rockfort Island was raided by the H.C.F. and caused a fateful
t-Virus outbreak which turned almost every inhabitant into a
Zombie. Thus, the only ones ever encountered in the wild were considered prototypes.
Only one living specimen was ever found on Rockfort Island and was eventually killed by
Chris Redfield. No other research ever continued with the Gulp Worm after this point, it's clear the experiments lived and died on the island.
It's possible all the research was taken by
Albert Wesker after he recovered data from the island, but no worm-related creatures have been seen since.
