In Requiem you step into the shoes of Bolen, a thief living in a sprawling medieval city. As the game starts, your most reliable fence has just sent you an urgent note telling you to come over to his house. You have no idea what he has in store, but with the sun setting it sounds like you might be in for an interesting night.
Requiem is a companion piece to Shadowcursed (but has a totally new story) and is free for anyone to download and play. All you will need to have installed is a copy of The Dark Mod (also free).
Here are the automated installation instructions:
Step 1: Download The Dark Mod. You can find it here: http://www.thedarkmod.com/download-the-mod/
Step 2: Once you install the Dark Mod, you can press the 'New Mission' button, then click on 'Download Missions' and select Requiem to download. It should then automatically install and you can play.
If you are new to Dark Mod levels (or first person games in general), I would recommend first playing the Training Mission which comes along with the game first.
Here are the manual installation instructions:
Step 1: Download The Dark Mod. You can find it here: http://www.thedarkmod.com/download-the-mod/.
Step 2: Download Requiem. You can find it at the following sites:
Step 3: Create a folder in your Dark Mod install with the path "darkmod/fms/requiem" and place the downloaded .pk4 file inside. When you load up The Dark Mod, the mission will appear on the "New Mission" page.
Feel free to shoot me any questions if something doesn't work or if you are stuck. You can also see the thread I set up for Requiem in the Dark Mod forums here.