Multiplayer mod Zxc by 291 (Blender.pro) for Half-Life 1 with free source code. Over 30 different weapons (including old), features and relatively high stability of the HLDS.
ZXC Mod 1.36 Final version (unreleased, from zxc albanian mod main server) including needed sprites, models sounds, etc. and the source code (now fixed for latest steam hlds version).
Might improvements which are to list and could put all modes, all modes of each weapon fired , there are many who are not as conosco not activate :v