During the ensuing chaos, Wesker injected himself with an experimental virus given to him by his partner, William Birkin.
[14] After allowing the Tyrant to "kill" him, the virus reanimated his body after the room became empty. This gave him superhuman strength, agility and regeneration, but at the severe cost of the loss of his humanity. The resulting mutation also gave him gold-red cat-like eyes (but these were not immediately noticeable, due to the sunglasses he always wore). Wesker was revived, while the remaining S.T.A.R.S. operatives were convinced that the Tyrant killed him. After reviving, Wesker realized the S.T.A.R.S. had destroyed the Tyrant and escaped with their lives. He then tried to steal the data from the laboratory and escape.
Wesker found that Sergei had downloaded the data to the U.M.F-013 and the
Red Queen had locked him from the mainframe system. He swore revenge against the remaining S.T.A.R.S. members, Sergei, and the Red Queen. His plans foiled, Wesker resolved to escape the mansion before the self-destruct timer ended. He was forced into a battle with the remaining B.O.W.s on his way to the exit, and praised his new immense powers when his enemies were swept away with little effort. Wesker mused that he hoped Chris and Jill would live long enough for the three of them to have their "tear-filled reunion", laughing evilly at the thought of seeing them again. He also had to deal with Lisa Trevor, who first approached Wesker outside an elevator leading to the surface from the lab.
