Also, I don't think MCP is being maintained anymore; their website has been "under construction" for years, and they haven't even updated to 1.12.2 (the latest patch update is generally the most popular for mods for that version; e.g. 1.6.4, 1.7.10, 1.8.9, etc), much less more recent versions (nothing at all for 1.13 or later). They also moved to a new website earlier, with all versions older than 1.6.4 removed (they probably only kept 1.7.10 after the next move because it was still relatively popular).
Hello, people!
How long ago MCP's site is under construction?
I want to download an old version of MCP.
You can find versions going back to Alpha here (they even have 7 different releases for Alpha 1.1.2_01, though only the latest should be used):
https://minecraft.gamepedia.com/Programs_and_editors/Mod_Coder_Pack#Downloads
Also, I don't think MCP is being maintained anymore; their website has been "under construction" for years, and they haven't even updated to 1.12.2 (the latest patch update is generally the most popular for mods for that version; e.g. 1.6.4, 1.7.10, 1.8.9, etc), much less more recent versions (nothing at all for 1.13 or later). They also moved to a new website earlier, with all versions older than 1.6.4 removed (they probably only kept 1.7.10 after the next move because it was still relatively popular).
TheMasterCaver's First World - possibly the most caved-out world in Minecraft history - includes world download.
TheMasterCaver's World - my own version of Minecraft largely based on my views of how the game should have evolved since 1.6.4.
Why do I still play in 1.6.4?