Resident Evil Wiki
Resident Evil Wiki
(Rejected BIOHAZARD/Resident Evil sequel)

The Clay Virus was the name used to refer to at least four viral strains developed during Umbrella's viral research.

The concept became obsolete with the involvement of Noboru Sugimura (Flagship) in the script of Resident Evil 2, and by the release of Resident Evil CODE:Veronica. The Progenitor virus replaced it and continued to evolve up until Resident Evil 5.[1]


The virus existed in four types: α (Alpha); βI and BII (Betas '1' and '2'); and ε (Epsilon).

The α-type was used to create the aquatic B.O.W. known as Neptune.[2] The βI-type was used to create the canine Cerberus B.O.W.,[3] while the βII-type was used as a bonding agent to create the Hunter .[4] The "ε"-strain was synonymous with the t-Virus that infected the Arklay Laboratory's staff.[5]

Further notes[]

  • The initial concept remains in the series, but its name, history and characteristics were altered several times by Noboru Sugimura until its final form in Resident Evil 5.
  • Information on the virus was released in the INSIDE OF BIO-HAZARD guidebook and its Directors Cut re-release. An accurate translation of this information can be found on Project Umbrella .



  1. Resident Evil 5, Progenitor virus
  2. Takeo, Inside of BIO-HAZARD, p.49
  3. Takeo, Inside of BIO-HAZARD, p.41
  4. Takeo, Inside of BIO-HAZARD, p.53
  5. Takeo, Inside of BIO-HAZARD, p.39
  6. Hideki Kamiya Twitter post, 2011-06-22