COSOMGAME PRESERVATION
2026-10-26 / UPDATE 0.1.1

A story route that follows the game

The original Final Fantasy III player now has 145 objectives, including 127 automatic milestones that follow the current game and 18 clearly marked manual-only checks.

Story route coverage

The expanded route defines 145 milestones: 127 have automatic rules and 18 require manual-only marking. Every milestone still supports an explicit manual override. The route uses this U.S. version 1.1 cartridge. Automatic-rule coverage and actual gameplay verification have different limits, recorded below.

What changed

Replaced the original 36 broad manual checks with 145 objectives across ten chapters: 127 automatic story, quest and magicite milestones, plus 18 manual-only objectives without a separately verified persistent marker.

Automatic checks read the verified original game's saved work RAM without changing it. Three matching observations confirm progress; the current story chapter rises above older unfinished tasks. Earlier snapshot loads remove later automatic checks, and detection pauses during session operations, hidden pages and rewind before following the current game again.

Explicit manual true and false choices override automatic results. Follow game restores tracking for an individual step. The previous 36-step checklist remains separate and unchanged, and checklist import/export retains its true and false choices alongside the new guide.

Route and Completed views, search across future and optional objectives, chapter details, keyboard focus preservation and phone layouts make the expanded guide usable while playing. The original ROM, core, save formats, time controls and cheats retain their existing identities.

What was verified

Genuine original-game input opened the Narshe mine gate and changed event bit 012C from unset to set. Before/after RAM witnesses and the original event command were checked; this test used no forced game flags or ROM patches.

Nineteen detector/source/real-RAM checks and eight manual-choice boundary tests passed. Independent review checked 110 original event setters and all 27 esper ownership predicates against the retained source, including the Odin-to-Raiden upgrade and later-story flag retention.

The actual updated browser player verified its ROM/WASM binding and the exact milestone-data hash. A synthetic Whelk flag fixture exercised automatic checking, three-sample confirmation, earlier-state rollback, manual override and Follow game; these fixture checks are not a Whelk gameplay claim.

Final browser checks covered legacy checklist import/export, invalid-import rejection, keyboard focus, future-objective search, desktop and phone widths. The original Save count increased from zero to one in a generated Narshe fixture, and the downloaded session passed independent complete-file readback and identity decoding. All generated browser storage was restored to its captured baseline.

Remaining limits

Eighteen objectives remain manual-only, including certain bosses, party outcomes and final victory. The guide total includes optional and missable objectives and is not the game's completion percentage.

The Narshe gate is the original-input gameplay witness. Other automatic rules are source-reviewed and fixture-tested; this release does not claim a complete campaign playthrough or every branch played in the browser.

Rewind pauses observation and then recomputes the currently loaded flags. The new browser rollback test used a supported earlier-snapshot import; the existing native time-control verification remains unchanged.

Reopened file handles can be read-only on this host. Use Allow updates when supported, Save as with a new filename, or a download copy. The new save regression tested download fallback; the earlier same-file write/readback proof remains retained.

Play Final Fantasy III · Coverage report · Release manifest