Technically it was still playing
1,529 karma · joined September 8, 2011
Or, return to dark Castle is now available on steam as mentioned elsewhere in this thread. It contains all the dark castle and beyond dark castle levels plus many more new levels and works on modern computers.
It's not an actual MCP. It's just built into the UI.
Anthropic has a lot of stuff that's way more difficult to use because of bad UI, spread over lots of different places.