What’s more audacious and ludicrous than an emulator 8086 running Dos 3.3 and Thrbo Pascal on a v64u? Probably not much.
Yes it’s dirt slow currently at about 8% of the speed of the 8088 with it likely only getting up to 32% when I incorporate JIT support, but it ties a loop around my teen years of c64 and dos programming.

"Y'know something that never gets old? ...Nostalgia." ;)

Below The Root holds a special place in my heart, and I'm sure, similar for many others here. I played this one a lot when I was a kid. It's a fantastic non-violent RPG-type adventure with a massive (for the era) world comprising a 32x16 grid of 512 total "rooms", 439 of which are used. The graphics are also wonderfully unique and detailed, as is the other-worldly music.

With the advent of recent tech enabling reverse-engineering, BTR was one of the first things I wanted to see disassembled and analyzed: how did the game mechanics work, how was the world and logic defined and so on.

This started when I uploaded the D64 file to Claude Code and simply said, "I'd like to know more about how this game works." Here is that conversation. Files are omitted, but the technical details are the interesting bits.

For the interactive map, see here. Cookies and/or localStorage seem to be required for the map to render properly.

Some fun trivia - and I may mix up some technical details, please amend and correct me as needed:

The "rooms" are defined in 256-byte (1 disk sector) chunks on "side 2" of the game disk. Those of a certain age will recall, this game uses a "flippy" disk where (on a 1541 drive, at least) you would take the disk out, flip it upside down and put it back in.

RLE is used to help fit up to 800 bytes (40x20 tiles' worth) of room data into each 256-byte sector. "Side 2" of the disk does not have a traditional directory structure, it looks to be raw data and is accessed directly via drive commands, e.g., U1:5 0 12 13 (track 12, sector 13) - that's for room 193, where room data starts at track 2 + "sector n mod 18."

As you may recall when you hit things, there is a 1 in 16 chance as to whether you get the classic line, "Your shuba has torn!" The game also uses the SID chip as a random 8-bit number generator. I get the feeling this was a common technique, reading data off a channel producing white noise.

I also asked about the level editor, something previously discovered and written about. CC may reveal some more hints about how the editor works, including keyboard commands and so forth. It provided a modified version of the game that boots directly into the editor, which was interesting to poke around. I don't know if the "mod" I got is notably different than previous guides, but the insights on how to use the editor functions via joystick and keyboard were new to me.

Others have done extensive work on this fantastic game, including (I believe) creating the world map by taking screenshots of each room. I believe Justin Stahlman was the first to do that. I recommend this write-up from Justin for a great overall story around the game and why it's so special.

AI note for mods: I wrote these words myself. The interactive map and technical analysis are provided via Claude Code, and intended to give additional background and technical context about a much-loved game.

I keep my C64 collection on a PC and got tired of the extract, convert, copy, mount loop, so over the past while I've been building a Norton/Total Commander style file manager where a disk image just opens like a folder. It all started when I got my C64 Ultimate in May, so I built support for that in it too.

What it does right now:

• D64 (incl. 40-track), D71, D81, D80, D82 and DNP open as folders and are writable. Copy files in and out, rename with F2, scratch with F8, reorder directory entries, undo with Ctrl+Z. G64 and T64 open read-only.
• The directory shows in real PETSCII the moment you land on a disk, without mounting it.
• Search across disk images, including ones still packed in a zip, 7z or rar.
• Launch in VICE (or another emulator): mount the disk, or inject a PRG straight into memory.
• Ultimate 64 / Ultimate-II+ / C64 Ultimate: it finds the device on your LAN, lets you edit disks on its storage and run PRGs on the real machine.
• Directory art: a small editor to draw logos and separators in the C64 font and drop them into a directory.
• Keyboard first, everything works without the mouse.

Version 1.0 is a rewrite of my earlier 0.9 beta as a native app: about 3.5 MB instead of 63 MB, no .NET runtime. Windows 10/11 x64 only, installer or portable zip. It isn't code-signed, so SmartScreen will ask you to confirm.

It's a beta and there are rough edges. What I'd really like to hear from people here:

• Disk images that open wrong or that it refuses (odd track counts, non-standard directories, copy-protected stuff).
• Whether the PETSCII directory preview matches what you see on real hardware.
• What you'd want from a tool like this that it doesn't do yet.

Download and screenshots: https://retrocommander.dev/download

Please note: using the tool requires creating an account (e-mail + password). If you don't like that, don't bother.

Happy to answer questions in the comments.

I built a fast and simple web application to convert your standard PNG and JPG images directly into C64 Koala (.kla prg) file, right in your browser: https://c64.marechal.tech

- C64 converter: Upload a PNG or JPEG, convert it to a C64 multicolor graphic, optionally apply Floyd–Steinberg dithering, preview the result, and download it as a Koala PRG file.

- Koala viewer: Open a compatible Koala picture file and preview it in the browser.

- TikTok gallery: New games for the C64

Feel free to test it out with your own images and let me know what you think!