It's December, and that means it's time for the monthly update!

• There's a message here, addressed to you.
  
  
• M868 Flamer Unit: Adjusted friendly fire damage and duration on normal friendly fire difficulty. (Thanks, ModdedMarionette).
  • Hardcore friendly fire is unchanged.
    
  • Friendly fire with a flamethrower now once again ignites immediately.
    
  • Damage now scales up linearly rather than slower at the start and faster at the end of the burn duration.
    
  • Afterburn duration is decreased by the amount of time since the previous friendly fire incident, minus two seconds.
    
  • Maximum afterburn duration is 100%, and minimum is 18.75%.
    
  • This means the minimum burn time for friendly fire with default game rules is: Easy: 1.125s, Normal: 1.5s, Hard: 2.25s, Insane and Brutal: a little over 2.8s.
    
  • Afterburn from friendly fire is now counted as friendly fire in mission statistics.
• Chainsaw: Lag compensation is now disabled by default. (Suggested by WTF-8).
  
• Bot marines will use guns rather than melee when they have been damaged by multiple enemies in quick succession. (Suggested by WTF-8).
  
• Sentries that have ammo remaining now revert to box form when they are destroyed rather than being completely lost.
  
• Added several functions to the Director VScript interface for querying the list of NPC types. See the Valve Developer Community wiki for details. (Suggested by ModdedMarionette).
  
• Entities that push such as doors and trains now deal damage to non-boss aliens they are unable to push.
  
• Fixed a texture reference count issue with the LanguagePreference material proxy. (Reported by mutezero).
  
• Marine reservation time is now 2 seconds after an instant restart rather than the 30 seconds that a full map load provides. (Suggested by WTF-8).
  
• Added a new main menu background themed after the Nam Humanum campaign. (Thanks, mfz).

Alien Swarm: Reactive Drop will always be free, but that doesn't mean it doesn't take a lot of work from a lot of talented volunteers to make. If you can, consider making content for the Steam Workshop, reporting bugs, proposing code[github.com] improvements, translating[github.com] the game into your language, or sending a dollar to one of the people who made Alien Swarm: Reactive Drop possible. The IAF thanks you for your continued service, Commander.