First you need to download files here. Then you need to find your Killing Floor folder (...\Steam\steamapps\common\KillingFloor). Drag System and Textures folder in your Killing Floor folder. Start the game, select Killing Floor gametype, and map you want, and set difficulty to hell on earth. Click Mutators tab, then add Healing Pain, Hard Patriarch mode, and Super zombies. Start the game and enjoy.
NOTE: Only Super zombies are whitelisted, so if you use all 3 mutators, you cannot gain achievements or level your perks.
Super Zombies (made by scary ghost)
You will notice diffrence very fast. If you are for example running for stalker, she will no longer hit air, but she will damage you, and you will start bleeding. Husk will shoot non-stop so you better finish him off fast, and crawlers will jump like crazy.
Healing Pain (made by GMK| J1gS4w)
Every time siren screams she will hurt you and also heal all nearby specimens.
Hard Patriarch (made by Marco)
This mutator replaces patriarch with insane patriarch. He will fire his chaingun while moving, and shoot 4-6 rockets at the same time.
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