Many download links for new maps & mutators are in the linked lists that follow.

Current Map Whitelist: http://forums.tripwireinteractive.com/showthread.php?t=41919

Current Mutator Whitelist: http://forums.tripwireinteractive.com/showthread.php?t=34416

What does it mean to be whitelisted? According to KF-Wiki: Any content created or approved by Tripwire Interactive is added onto the official whitelist, which allows players to level up their perks.

Sami and I are fans of the Tachikawa and Defence-c1 maps. (If you're wondering, that is the British spelling of defense.) The Doom2-Final-V6 map is one of Ruth's favorites and is great for leveling perks. We also think the Hellfire's Husks only mutator is fun playing as firebugs for high flame defense while we use various weapons. The Faked Players mutator increases specimen numbers for more of a challenge.

Feel free to comment with your favorite whitelisted maps and mutators! We'd love to try them out!

The Wolf Pack Clan has created a mutator that includes their specimen creation, the Brute. You can download the mutator as well as a Brute themed map here: http://www.mostimpressive.nl/TheBrute/downloads.html

It's currently greylisted which means perks are enabled during gameplay but your progress will not remain after the game's completion. We expect it may be whitelisted in the future.

http://psteamproxy.yuanyoumao.com/video/1250/80475

WE'RE PLAYING THIS, K GAIZ?

4 MOAR DAYS!