This mod takes place in a researchs center called "White gate researches center". This center is similar to black mesa, it is under the ground, and it has security officers etc.. You play as an HECU soldier in this mod and you should search&destroy this center. This center is not filled with zombies or headcrabs or any other things. The researchers in the white gate researchs center, have found a way to teleport to Xen and they have xaptured some headcrabs. They have managed to take out a virus out of theese creatures and they are planning to make a biological weapon from this virus. But, they are not allowed to work on weapons, because government doesnt want them to do. But, unfortunately, they go on working on this bio-weapon and government learns this, so they ask HECU squad to moake an operation to the base and stop the developement of this bio-weapon. The commander, finds this mission easy, so he decides to send only one soldier to this center. And it is YOU! :D As i said...
Scientist Slaughterhouse: The Single Player Campaign.
A very unusual mod, in the sense that your enemies encompass Barneys, scientists and a itchysaur only. The mapping is very flawed, with remarkable things such as a spiral staircase you have to crouch-jump in.
I really liked the idea of going in and killing the scientists, like the HECU in original Half-life. I was all giddy as I clawed onto a window in which I saw a whole room of them evil scientists panicking. The best part of the mod is definitly that it isn't all just run & gun; the scientists barricaded themselfe and took to hiding, making the whole experience a puzzle game in which you have to find out how to reach every single one of them.
It is unfortunetly very flawed. Worth a go though for the unique experience.