Leon led the D.S.O squad sent to deal with the found clandestine bioterrorist laboratory. While his teammates were clearing the chambers harboring bio-organic weapons containing mutants and other creatures, Leon cautiously entered the laboratory section. He hoped to copy and delete all documented information about the experiments that were conducted there. As he worked on the computer, his gaze shifted around the room. He reviewed the area. His gaze fell on an upright tank. The shadow in the water resembled a humanoid figure. He decided to not investigate until his work on the computer was finished.