Tripwire Interactive has just announced the upcoming free expansion pack for their horror title game called Killing Floor. The new level, entitled "Foundry", is set in an old iron works which the Horzine Corporation has converted to support their top secret military projects. Exactly what they have been up to here is a matter for conjecture - but before they can send in investigators, your squad has to get in there and clean out the infestation of specimens.

To assist in your task, there are now two new weapons. The first is an old favorite of armed forces the world over: the AK-47.

In their case, it has the folding stock, for ease-of-use in close quarters. This one will fit in as a heavier weapon for the Commando Perk and provide extra stopping power over the base Bullpup. The second is a weapon that just about every special-forces soldier in every movie seems to know intimately, for no good reason other than personal interest: the Japanese Katana sword. Just where the squad got hold of it is a mystery, but this piece of Samurai history is just so fitting, such a thing of beauty and such a perfect melee weapon, that they aren't going to ask too many questions.

In addition to this free update, Tripwire Interactive will be releasing their first paid DLC character pack for Killing Floor very soon. This character pack adds four new playable characters including a Horzine foundry worker and a soldier in prototype Horzine body armor.