Sierra Game Compiler
AGI-64 for C64 · AGI-ANTIC for Atari · Native games
Sierra Game Compiler for Windows builds seventeen native adventures for C64 and Atari XL/XE, including Space Quest: The Lost Chapter. The original computer’s own CPU runs the game, with no cartridge processor assistance. Free Windows or Mac tool; bring your own commercial game files.
Free · Windows v1.1.16
The original computer does the work.
Prepare the game on Windows or Mac, transfer the cartridge image, then play on your classic computer. Its own CPU runs the game; the cartridge supplies storage. Your preparation computer is not required while playing.
C64: use a cartridge supporting the selected format and capacity. AGI images use 1 MiB or 2 MiB; native Another World requires expanded 4 MiB EasyFlash support.
Atari: XL/XE with 64 KB RAM, or an upgraded Atari 800, and the selected cartridge format. KQ2, Police Quest and SQ2 require MegaMax 2 MB capacity.
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King’s Quest I · C64 — High-resolution dialog text at King Edward’s castle. Fresh capture from compiler 1.1.13 in VICE.
Choose a thumbnail or use the arrows. Select the large image to view it full size.
Sierra adventures on a 1 MHz machine
AGI-64 is available now. The free Sierra Game Compiler for Windows 1.1.16 brings fourteen original Sierra AGI titles and three fan-made adventures to the Commodore 64. The same download includes AGI-ANTIC, supporting 17 adventures for Atari 8-bit computers.
There is something special about exploring Daventry or stepping aboard the Arcada on a classic machine. AGI-64 brings these adventures to the C64's own display, sound, keyboard, and pace.
Download the free Windows compiler · v1.1.16. AGI-64 downloads and compiler updates are available from meanhamster.com.
Download for Mac (Apple Silicon) · v1.1.15 · macOS 14 or newer
New in Windows 1.1.16 · October 13, 2026: Space Quest: The Lost Chapter by Vonster D Monster joins the C64 and Atari XL/XE lineup. Select the supported version 10.0 AGI fan-game folder to build a C64 CRT or Atari CAR.
Atari arrow keys now work without Control for walking, menus and inventory. Control+arrows continue to work. The first-use guide is retained; follow the native game tutorial for setup, expected editions and cartridge requirements. The published Mac release remains 1.1.15.
Coleco ADAM performance improvements improve rendering, data transfers, caching and event processing in its Highly Experimental games.
The Atari controls from 1.1.14 are retained: Control+1 through Control+9/0 handle the original function-key actions, HELP handles F1 and TAB opens inventory/status where supported. Menus and game messages show the correct Atari controls, and longer help labels fit their authored rows without clipping or wrapping, including King's Quest I's help screen. Source-layout compatibility and the Space Quest I C64 cartridge display name repair are retained.
King's Quest I and Space Quest I also support MSX2, Coleco ADAM and TI-99/4A. These three systems remain Highly Experimental: packaged builds have been checked, while full-game and real-hardware testing remain open. All five systems build directly on Windows or Mac.
The compiler retains the walking and drawing optimizations, Normal C64 timing improvements, unused-code trimming, PAL C64 keyboard repair and Space Quest I title-animation repair from 1.1.13. Existing saves remain compatible.
C64 menus, dialog boxes and command input use high-resolution text alongside the original color artwork.
Atari 800, welcome to Daventry!
Explore The Black Cauldron, Donald Duck's Playground, Gold Rush!, Mixed-Up Mother Goose, King's Quest I, King's Quest II, King's Quest III, King's Quest IV (AGI edition), Leisure Suit Larry, Manhunter: New York, Manhunter 2: San Francisco, Police Quest, Space Quest I, Space Quest II, Space Quest 0: Replicated, King's Quest VI AGI demake, Space Quest: The Lost Chapter through AGI-ANTIC. The Atari's colors and character give Daventry a look of its own, and seeing Graham outside the castle on another of our favorite machines is a real treat. AGI-ANTIC is included in the same free compiler, with all 17 adventures supported.
AGI-ANTIC minimum requirements: Atari XL/XE with at least 64K RAM, or an Atari 800 with an Incognito board or similar upgrade. King's Quest II, Police Quest and Space Quest II require a MegaMax 2 MB cartridge.
Bring your own game files
You must supply the original game data from your own copies. No Sierra games or game data are included. Choose a source folder in the compiler; it checks the game and edition before building. Use the original AGI editions in the supported list below.
For the C64, choose 1, 2 or 4 MB EasyFlash, or 2 MB MegaCart / Magic Desk 16K. Expanded EasyFlash images need compatible hardware and firmware; our upgrades support them on TeensyROM+ and Kung Fu Flash 2. See the cartridge requirements and the compiler's Help for setup and controls.
Supported games
Commodore 64 · 17 titles
- The Black Cauldron
- Donald Duck's Playground
- Gold Rush!
- Mixed-Up Mother Goose
- King's Quest I
- King's Quest II
- King's Quest III
- King's Quest IV (AGI edition)
- Leisure Suit Larry
- Manhunter: New York
- Manhunter 2: San Francisco
- Police Quest
- Space Quest I
- Space Quest II
Plus three fan-made adventures: Space Quest 0: Replicated, King's Quest VI AGI demake, Space Quest: The Lost Chapter.
Atari 8-bit · AGI-ANTIC: The Black Cauldron, Donald Duck's Playground, Gold Rush!, Mixed-Up Mother Goose, King's Quest I, King's Quest II, King's Quest III, King's Quest IV (AGI edition), Leisure Suit Larry, Manhunter: New York, Manhunter 2: San Francisco, Police Quest, Space Quest I, Space Quest II, Space Quest 0: Replicated, King's Quest VI AGI demake, Space Quest: The Lost Chapter are supported.
MSX2, Coleco ADAM and TI-99/4A · Highly Experimental: King's Quest I and Space Quest I. MSX2 needs 64 KB RAM and a V9938/V9958 with 128 KB VRAM. ADAM needs 128 KB total RAM. TI-99/4A needs the standard 32 KB RAM expansion. See the game and system compatibility chart for source editions and requirements.
Other Games for C64
The same compiler also builds native C64 versions of Another World and M.U.L.E.+. Another World uses your original Amiga game files and requires a compatible 4 MiB EasyFlash setup. M.U.L.E.+ is included, with optional SID music support. Both run on the C64's own CPU.
Support applies to the game editions recognized by the compiler. If your files are not recognized, check the source edition before building.
Built to look its best and load fast
AGI-64 includes a custom background pre-processing technology that keeps the original artwork looking its best, loading fast, and working well on our 1 MHz best friend.
In the news
- The Space Quest Historian Playing Space Quest 1 for C64!
- AGI-ANTIC game demos on YouTube
- Read The Oasis BBS's AGI-64 coverage
- Read the AGI-64 story on Zeli
- Join the Hacker News discussion
- Read Adafruit's AGI-64 coverage
- This Week in Retro 288: AGI-64 and Sierra adventures on C64 and Atari
Downloads, updates, and help
Download Sierra Game Compiler for Windows 1.1.16, then use its update check for future releases. If you find a problem, the compiler's Report Bug button opens our contact form, where you can include a screenshot.
Download for Mac (Apple Silicon) · v1.1.15 · macOS 14 or newer
Report an AGI-64 issue · Read the launch news · Earlier development update
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Mean Hamster Power Engine for 8-Bits
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ZipZork
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Shadowgate for C64
Coming soon to Commodore 64: explore Shadowgate with mouse controls and a graphical inventory. Future access will be through AGI-64.