The Left 4 Dead Blog has details on the return of the Gib Fest mutation for Left 4 Dead 2, saying: "For our coop mutation this week we return to everyone’s favorite Gib Fest. Simple, go play." They also announce they are also "featuring" Realism Versus, saying: "This week we added quicker spawns for the infected. If you haven’t played recently, you are missing out on one of the most intense Left 4 Dead 2 competitive experiences. It is like regular Versus but no health kits in the world, no glows on fellow survivors, harder to kill commons and now faster Special Infected spawns (coming soon to the 360)." Steam News has the accompanying patch notes that include balance tweaks in addition to the mutation, saying: "The following changes are for the PC and will be available for the XBOX 360 in a future update." The patch notes follow.

Updates to Left 4 Dead 2 have been released. The updates will be applied automatically when your Steam client is restarted. The major changes include:

• Encore Mutation: Gib Fest!

The following changes are for the PC and will be available for the XBOX 360 in a future update.

Competitive Modes

• Removed Special Infected spawn music in competitive modes.
• Added a glow outline to the witch, visible only to the infected team.
• Added cvar “director_allow_infected_bots” for confogl and other configs.
• Survivor health glow changes:
  • Adjusted glow color transitions to match movement speed transitions.
  • Use combined regular and temp health when calculating glow color.
  • Glow pulses slightly when the Survivor is on temp health.
• Realism Versus
  • Cut Special Infected spawn times by half in Realism Versus.

All

• Fixed limping Survivors moving slightly faster in water.
• Fixed voice recording intermittently stopping on Mac OS X
• Client-side plugins
  • Clients must run with –insecure to load unsigned plugins.
  • Insecure clients cannot connect to secure servers.
  • Servers can opt to allow insecure clients by running with –insecure.
  • Secure clients can connect to both secure and insecure servers.