Tripwire continues to create reasons to hop back into its four-year old co-op shooter. After bestowing a low-grav moon base map last Christmas, Killing Floor kicks off a new holiday event tomorrow, the Summer Sideshow Pier of Pain, bringing with it the first new mode since it released.

“Objective Mode” layers tasks like VIP escort and item retrieval atop Killing Floor's standard, wave-based monster killing. The mode is initially playable on Steamland, a new map, but Tripwire is also including mod tools in the Pier of Pain update for the game's community to create more Objective Mode maps. Tripwire invited me to an exclusive playtest of the map earlier today, shown in the video above.

Killing Floor will be free to play for a week beginning July 4. New weapons and skins are also packaged in the update as unlockables or DLC, shown below.

Community Steampunk Weapon Pack



The Orca Bomb Propeller - The Orca Bomb Propeller tosses little delayed explosive bombs. Good for those bank shots!



Multichamber ZED Thrower - A steam-powered lead launching auto shotgun, with a secondary steam discharge that will knock enemies away!



Single Piston Longmusket - A finely crafted long rifle from the Victorian era fitted with telescopic aiming optics.



Dr. T's Lead Delivery System - Thy weapon is before you. May it's drum beat a sound of terrible fear into your enemies.



Golden Gun Weapon Pack 2