Lieutenant William "Bill" Masterson is a character that has appeared in some form or another in the original Killing Floor mod, as well as both the first and second retail games.

There is also a "classic" version available in Killing Floor 2 for people who own the first game.


In the original mod, his first name was David and he was a Sergeant. In the Story mode, your character is trying to track him down in the aftermath of the outbreak and his squad's death.

Ultimately, you encounter him in the depths of a secret lab where it is revealed that he was a clone created by Horzine and is responsible for the death of his squad and now intends to kill you. He then serves as the final boss for the story mode.

Patch 2.5 introduced a good Masterson clone as a playable character.

It is unclear whether there was ever a real David Masterson, or if they were intended to be clones of Kevin Clamely's son like many of the other specimen he created.

In-Game Description

When a DRF Specialist infiltrated the Horzine Biotics Laboratory and killed the Masterson Clone, that was the last anyone thought they would see of the man. Ironically, it was weeks later that another team found a working incubator in the derelict lab with his genetic footprint. The result was a fully functional clone, who now aids the DRF in putting down the remaining failed specimens.

Killing Floor

Now listed as a Lieutenant, Masterson returns in the first retail release with no first name given. It is unclear if his history from the original mod about him being a secret Horzine project intended to destroy the opposition from within remains in tact or not. His biography does reference him seemingly coming from nowhere, but that may just be an in-joke referencing the original mod.

In-Game Description

It's unclear how this man rose through the ranks so quickly; his prior military service seems virtually non-existent. One thing that's clear is that he's a man of few words, and has an unnaturally calm demeanor in combat situations. He directs his men decisively, and always gets the job done - no matter how unsavory.

Killing Floor 2

Masterson again returns in Killing Floor 2, now given the first name of William or Bill. Additionally, owners of the original Killing Floor are given a "Classic Masterson" character as well.

In-Game Description

Bill Masterson had a checkered career in the Army. He wanted heroic soldiering, against bold and evil enemies of Queen and Country, but what he got was a bunch of dirty terrorists. He wanted a good shooting war, but what he got was leading his men through a series of stupid "police actions" in crappy parts of the world. So he quit. After a couple of worthless jobs, he woke up one morning to the Apocalypse going on in the streets of London. Masterson, now the heroic soldier he wanted to be, let himself in to the local Reserves barracks, tooled himself up, and started his own shooting war. It wasn't the war he had expected or trained for, but it worked. And he is bloody good at it!

Classic Masterson Description

No-one has ever really understood how this Masterson rose through the ranks at all, although some have suggested his richer and better-looking cousin, Captain Sir Richard Wiggins, may have had some influence. Or perhaps it was his smarter brother. But, as is always noted, he's a rough diamond, a man of few (polite) words and has an unnaturally calm demeanor in combat situations. Pretty much everyone reckons this is due to his lack of imagination, empathy and intelligence. Luckily, he directs his men decisively and always gets the job done - no matter how unsavory that job would appear to anyone with good taste or decent manners.


  • Classic Masterson in Killing Floor 2 has the original voice actor from the first game. All the male characters except Reggie the Rocker shared the same two male voices. Classic Briar has the other original voice actor.
  • With Classic Masterson's description, his canocity is unclear. He may just be a bonus, or he may be a separate person from the default Masterson.
  • Alan Wilson, who provided Masterson's voice in the first Killing Floor and Classic Masterson's voice in the second Killing Floor, is the vice president of Tripwire Interactive. Classic Masterson's face is modeled after his.
  • In the first Killing Floor, Masterson's face was modeled after Mike Munk's, a developer at Tripwire Interactive.


Killing Floor Mod

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Killing Floor

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Killing Floor 2

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