There has been several implementations of Forth that were running on, and targeting, the C64. Were there any commercial software releases (not throw-away hobby projects or in-house utilities) that were implemented in such a Forth system? The more widespread the better; my favorite would be if there was a released game.
Amnesia (Electronic Arts) is probably the most famous one. The King Edward Adventure Game system was just a wrapper.
Hard Hat Mack (Electronic Arts) copy-protection was written partially in Forth.
Among educational titles, Davidson and Associates published a few, like Alge-Blaster and Read 'N Roll.
I wrote C64-Forth way back in the early 80's (we sold it to Commodore but they disbanded their software products group shortly thereafter and it never made it out of the loading dock). Had some interesting users of it, including Lawrence Livermore Labs.
Portions of it were in assembler. All the math was implemented by calling the C64's internal ROM math code, so it's fast. I did one unusual thing - I stuck with C64's normal file structure. This meant you didn't need Forth-formatted floppy disks - in Forth, you could read and write normal data files, and you could read/write C64-Forth data from Basic or assembler.
Should anyone come across a copy of it, I still have a manual for it. I'd consider scanning it in or photocopying it. Gregg
Update: Following advice below, I have scanned in the manual (to two PDF files) and uploaded them to: https://archive.org/details/c64forthmainmanual. I will occasionally monitor this thread and would like to hear from anyone who actually runs it (I don't know if the version available at the site named below has copy-protection defeated. It may not be runable as is). If someone wishes to have a more extensive discussion of their experience with it, leave a message here, I'll create a temporary email address and post it here, and we can keep in touch.