(Covers information from Anderson's universe)
"One of The Hive's early experiments. Produced by injecting the T-Virus directly into living tissue. Results were, unstable. Now that it has fed on fresh DNA, it will mutate. Becoming a stronger, faster, hunter."
The Licker is a biological weapon created by directly injecting the T-virus into live human tissue.
The first known Licker was a cluster developed within The Hive, one of the Umbrella Corporation's bio-weapons laboratories. One Licker was released from confinement to hunt down Umbrella's "Sanitation" taskforce by the Red Queen to prevent an outbreak of the virus spreading beyond the laboratory itself. The Licker killed Spence at the train platform, and after feeding on his body, mutated into a new form. The Advanced Licker then proceeded to follow Rain; Alice; Matt Addison and Chad Kaplan. The creature threw Kaplan straight out of the train, likely killing him, and scratched Addison, infecting him with a mutant strain of T-virus. Matt and Alice killed the Licker as they escaped from the train.
In a second attempt to access The Hive, Umbrella inadvertently released the Undead and a number of Lickers into Raccoon City. A number of these Lickers took shelter at Raven's Gate Church, where they were killed by Alice while hunting a group of survivors.
Rather than underwent V-ACT process as with in the game series, Anderson's iteration of the creatures are created through direct administration of T-Virus into live human tissue. However, the resulted mutation remained same: The skin is completely shed off, exposing the overdeveloped muscle that endowed them stronger fighting abilities than either humans or ordinary Undeads. In addition of this, the skeleton is altered into much bestial form which forced the Lickers to walk on all-fours, but at the same time benefits them with body that optimized for speed and agility along with razor-sharp claws to climb walls and ceiling like lizards as well as doubles as deadly melee weapons. The tongue also developed further by the same mutation, giving it the ability to grab things from distance and even whip through flesh like a hot knife against butter.
Because of the eyes' degradation from their mutation, the Licker's "vision" is made up of a dull 3D mapping of where their senses originate, similar to a thermograph. Combined with their enhanced hearing, their senses take the form of a radar or sonar, allowing them to still perceive his environment more clearly.
An animatronic model was created for the first Resident Evil film, with CGI enhancements and a tongue added in post-production. Another animatronic was created for Apocalypse, but special effects supervisor Alison O'Brien found it to be inadequate and switched to full CGI. This required the special effects team to examine meat at a marketplace to get the right texture and colour for what O'Brien described as a "flayed human".