Modifications and Add-Ons

The Bullseye Crosshair Collection :

- Includes modifications for the Quake Series and Half-Life.
Cooltech Games :

- Patches and modifications for Half-Life, Unreal Tournament, and Quake.
Crosshair Central :

- Provides crosshairs for Central, Quake 2, Half-Life, Counter-Strike, Sin, and Kingpin, tools, and tutorials.
DAV Levels :

- Levels and maps for Doom2, Heretic, Hexen, Half-Life, Quake and Quake2.
Foyleman :

- Soldier of Fortune, Serious Sam, and Return to Castle Wolfenstein.
Garjen Software :

- Add-ons, custom levels and utilities for games such as Duke Nukem 3D, Wolfenstein, and Lemmings.
Grey Fusion :

- Tips and ideas for editing game engines for Half-Life, the Quake Series, Red Faction, and the Unreal Series.
M Planet :

- Includes mapping and level editing instructions, and downloads.
The Mastahuka Page :

- Offers maps for games including Half Life, Unreal Tournament and Blood.
Mirage's Maps :

- Maps for Half-Life and Quake 3.
Poly Count :

- Includes downloads, modifications and game resources.
Slacker's House :

- Unreal Tournament, Unreal Tournament 2003, and Quake 3 maps.
Super Capture the Flag :

- Includes game modifications, downloads and information. Plays on Quake and Half-Life.
Total Conversions.com :

- Deals with modifications to games developed by 3DRealms.
Ultimate Mapping :

- Maps for Counter Strike and Battlefield 1942.
Vondur's War Supply :

- Includes custom maps for Quake, Quake2, Quake 3 Arena and Half-Life.
VR21 :

- Offers modifications and add-ons for several games, including Doom and Quake.
Wavelength :

- Focuses on editing and game modification in Half Life, Quake and Unreal series games. Includes downloads, tutorials and utility downloads.