The creation of the Licker B.O.W. has varied across different mediums, but according to Resident Evil's in-game canon, they were originally created after human T-virus carriers were subjected to secondary infection in a controlled environment. The results were unstable, but months of continued testing resulted in the production of a viable living weapon. The Licker's appearance is truly horrific: multiple layers of skin have receded and torn, exposing the majority of the creature's muscle tissue. Its hands and feet have altered to sport a series of long, razor-sharp claws that allow the creature to crawl on floors, walls and ceilings as well as rip its prey to shreds. Perhaps its most disturbing feature is its head: it has no eyes, no visible nose or ears, its brain is exposed and its mouth is filled with sharp teeth. The Licker derives its name from its tongue, which can extend several feet and is strong enough to impale or decapitate human prey.
- The Licker has a quadrepedal bone structure and is more accustomed to moving on all fours. It is highly agile and can jump great heights and distances.
- Though it has no visible ears, the Licker has super-sensitive hearing and relies on this sense to track its prey.
- Lickers don't have eyes, making them completely blind, however their heightened sense of sound compensates for this.
- Exposed brain tissue means greater vulnerability to attacks aimed at its head.
- In S.D. Perry's novelisation of Resident Evil 2 entitled "City of the Dead", Lickers were supposedly created by experimenting on reptiles. Their serial code was stated as being RE-3, but the Lickers were never given serial numbers in the games.