Classic Offensive is a CS:GO mod with the goal of bringing back the community aspects and aesthetics of CS.
The mod unfortunately got cancelled...
Official announcement: x.com/csco_dev
More info on the official website classic-offensive.net.
You can still play the old beta version that has been published on ModDB.
If you have any problems with the installation, ask anyone for help in the #support channel on the Classic Offensive Discord server.
ModDB Beta version installation:
If you don't want to download CS2 or are a Linux/Mac user use this guide instead: CSCOGuide
1) Download "csgo_legacy"" from CS2 beta branches.
2) Download CO Beta 1.2.5c and 1.2.5d Patch.
3) Put the files inside "C:\Program Files (x86)\Steam\steamapps\common\Counter-Strike Global Offensive\".
4) Add "C:\Program Files (x86)\Steam\steamapps\common\Counter-Strike Global Offensive\csgo.exe" as a Non-Steam game.
5) Add "-steam -game cscomod/csgo -language csco" to the launch options.
6*) Replace the first line in "C:\Program Files (x86)\Steam\steamapps\common\Counter-Strike Global Offensive\csgo\steam.inf" with "ClientVersion=2000258".
* - Fixes connection to CSGO Network
I am not associated with Classic Offensive Dev Team.