Return to Zork / The Zork Anthology (Zork Legacy Collection, 1997) - findings

Established against a physical pressing read on an Apple Silicon Mac with a Pioneer BD-RW BDR-XS07U. The general method is in docs/imaging.md; this file holds what is specific to this disc.

Identity

Mixed-mode CD: one Mode 1 data track (volume RTZ_ZA, 94582 sectors) followed by 25 Red Book audio tracks, 211940 sectors in all, lead-out at 47:07.65. DISK.ID reads “Return to Zork CD-ROM / 1.2 / CD-ROM” and is dated 1994-09-29; the disc identifies itself as a Return to Zork CD-ROM, with the anthology added alongside. Mastering dates run to 1997-03-10 (AUTORUN.INF), so the disc is a 1997 pressing. 173 files; see zork-legacy-1997-rtz-anthology.ls.txt.

The pressing is Redump-verified, all 26 tracks. A full linear raw dump made 2026-08-29, split at Redump’s track boundaries and corrected for the drive’s +667-sample read offset, hashes byte-identical to redump.org disc 128285 (“Return to Zork / The Zork Anthology”, edition The Zork Legacy Collection, serial 1000028-104-U3, write offset 0) on every track; see checksums.txt. The data track matched with no correction at all; the audio tracks only after the offset shift, which is how the drive’s read offset was measured in the first place.

Structure

Three layers of different ages sit on one disc:

• Return to Zork, 1993 build. RTZCD.PRJ (43,016,792 bytes, 1993-09-15) is the same size and date as the copy on The Zork Anthology (1994), and the 84 .PMV movie files at root are all dated 1993. The 25 audio tracks are Return to Zork’s CD audio.
• 1994 installer layer. INSTALL.EXE/INSTALL.DAT (the Activision DOS installer) and the .RED archives RTZCD.RED, RTZCDDRV.RED and DRIVERS.RED, all dated September 1994 - but at different sizes from the 1994 disc’s (276,584 vs 130,683; 104,708 vs 101,827; 28,032 vs 27,847), so the RTZ install set was revised between the two pressings.
• 1997 Legacy Collection layer. A Windows InstallShield front end (SETUP.EXE, _SETUP.LIB, DATA.Z, UNINST.EXE), SPLASH.EXE with SP256/ button bitmaps, AUTORUN.INF, a 5 MB AVI/MOVIE.AVI (1997-03-10), Acrobat Reader in ACRODOS/, and the documentation as PDFs in DATA/ (FINAL.PDF 11.6 MB, MAPS.PDF, HINTS.PDF, all 1997-03-07).

Gaps and post-gap

Measured on the raw dump (2026-08-29): the ISO volume declares 94,430 sectors and the data track runs to 94,582, so the data track ends with 152 structured empty Mode 1 sectors - the standard two-second post-gap before the mode change, and nothing like the 61-second pad on the 1994 pressing. The 150-sector pregap before track 2 and the 150-sector pregaps before each of tracks 3-26 are all pure digital silence; in an uncorrected dump the first pregap’s tail carries the opening 2,668 bytes of track 2, displaced by the drive’s read offset.

The anthology games

Unlike the 1994 disc, where the games hide inside ZORKANTH.RED, here they sit as loose files under DATA/:

• Zork I, II, III in DATA/ZORK1..3/: interpreter _ZORKn.COM at 11,402 bytes (Doherty’s 3M2), NNANSI.COM, a DATA/ZORKn.DAT padded to 92,160 bytes, and a SAVE/ZORKn.DAT. Every file is dated 1995-05-31 except the saves.
• Zork Zero in DATA/ZORKZERO/: ZORK0.ZIP (300,032 bytes, r393), ZORK0.CG1 (244,507) and ZORK0.EG1 (333,654) plus ZORKZERO.EXE (47,494, interpreter 6.71) - byte-for-byte the same sizes as Masterpieces’ PC/ZORK0/, and again no .MG1 and no .EG2. The incomplete-graphics omission Doherty documented for LTOI1 persists on this disc too.
• Beyond Zork: BZORK.EXE (33,946 bytes, interpreter 5J) and NNANSI.COM sit in DATA/ dated 1996-06-21, but there is no loose BEYONDZO.DAT. The story file ships inside the InstallShield DATA.Z - along with a great deal more; see below.
• Real save files again. SAVE/ZORK1.DAT (12,883 bytes), ZORK2.DAT (12,213) and ZORK3.DAT (12,680) are dated 1996-06-11 and are byte-identical to the saves on Masterpieces, which carry a 1996-06-22 stamp - so one set of saves, made on or before 11 June 1996, was reused across both products.

Inside DATA.Z: fourteen unadvertised Infocom games

DATA.Z (2,835,304 bytes) is an InstallShield 3 archive - magic 13 5D 65 8C, 42 members in 12 directories, PKWARE DCL “implode” compression - and it is what the Windows SETUP.EXE actually installs from. scripts/isz.py lists and extracts it.

Its contents are the disc’s DATA/ tree again (the same 24 Zork I-III and Zork Zero files, byte-identical to the loose copies, plus BZORK.EXE and NNANSI.COM) and a DATA\ directory of 18 story files that is Masterpieces’ PC/DATA/ directory, byte for byte, every one timestamped 1996-06-22 01:41, Masterpieces’ mastering moment:

Ballyhoo r97.851218, Beyond Zork r57.871221, Deadline r27.831005, Enchanter r29.860820, Infidel r22.830916, The Lurking Horror r203.870506, Moonmist r9.861022, Planetfall r37.851003, Sorcerer r15.851108, Spellbreaker r87.860904, Starcross r17.821021, Stationfall r107.870430, Suspect r14.841005, Suspended r8.840521, The Witness r22.840924, Zork I r88.840726, Zork II r48.840904, Zork III r17.840727.

So a Zork Legacy Collection owner who runs the Windows installer receives the story files for fourteen Infocom games the product never mentions - no interpreters or documentation for them, just the padded .DAT files, playable in any Z-machine interpreter. The simplest explanation is that the 1997 installer was built from Masterpieces’ PC directory wholesale and nobody pruned the shared DATA/ folder. Beyond Zork’s story file, the one anthology game not loose on the disc, is identical to Masterpieces’ copy.

Open items for this disc

Resolved 2026-08-29: DATA.Z extracted; see the section above.

Resolved 2026-08-29: Redump verification, including the audio tracks.

Resolved 2026-08-29: the anthology files are the same builds as Masterpieces’. All 24 files compared against Masterpieces’ PC/ tree hash identical (SHA-1): the three Zork I-III sets (interpreter, NNANSI.COM, SETUP.INF, batch file, padded story file, and save), all four Zork Zero files, BZORK.EXE and the root NNANSI.COM. The story files are Zork I r88.840726, Zork II r48.840904, Zork III r17.840727 and Zork Zero r393.890714. The save files being identical settles their date: this disc stamps them 1996-06-11, so Masterpieces’ 1996-06-22 stamps on the same bytes are its mastering date, and the saves were made on or before 11 June 1996.