Monster Hunter: World keeps its main Steam PC progress in SAVEDATA1000. Because the file sits under an account-specific Steam userdata tree, the account context belongs in the backup record. Copy the file outside Steam before major changes and keep multiple dated revisions rather than relying on cloud synchronization alone. A future editor must handle account/profile semantics explicitly; Phase 23 only documents where the file lives and how to preserve it safely.
Identify the exact save you intend to edit
The researched Monster Hunter: World PC save location is Windows: <Steam-folder>userdata<user-id>582010remote | Linux / Steam Play: Steam Play: <SteamLibrary-folder>/steamapps/compatdata/582010/pfx/. Known file/folder pattern: SAVEDATA1000. Storefront context: Steam. The save is under Steam userdata, not the Monster Hunter: World installation directory. The numeric user folder identifies the Steam account context. Do not edit a similarly named file from a different profile, edition, or cloud cache.
Make an untouched backup first
Copy SAVEDATA1000 to a dated location outside Steam userdata. For extra context, record the Steam account/ID that produced the file. Keep that copy outside the live save directory and do not overwrite it with later experiments. Cloud context: Steam Cloud/remote storage is part of the normal PC workflow. Manual backups are still valuable because a damaged local revision can also synchronize. If a launcher can synchronize the save, prevent it from silently replacing either the original or edited copy while testing.
Understand the format boundary
The Steam PC profile uses the SAVEDATA1000 file under app 582010 remote storage. The file contains account/profile progress and should be treated as user-associated data rather than an anonymous portable save. File-extension context: No single extension is sufficient to identify every relevant save record. Compatibility note: Third-party save transfers often need Steam-ID-aware handling. This Game Hub does not claim that a SAVEDATA1000 file from another account is directly portable. These facts help identify the save but do not automatically reveal every field, checksum, encryption rule, or version-specific structure inside it.
Use only a Tool whose claim matches the file
Generic viewers and diff tools can inspect bytes without claiming game-specific semantics. A game-specific editor should be used only when its Tool page explicitly lists Monster Hunter: World, a matching supported version/container, and a Verified operational runtime. A planned URL or Game Hub is not evidence that an editor exists.
Test the edited copy safely
Write to a new output file when the Tool supports it, keep the original backup, restore the edited copy into the correct profile/storefront location, and launch the game only after the file operation finishes. If the game rejects it, If progress is missing after a cloud conflict, preserve both the current remote/local file and any backup before trying replacement. Avoid repeatedly launching the game while deciding which copy is authoritative. Return to the untouched backup before trying another change.
Verification context: The Steam userdata path was reviewed against current PCGamingWiki coverage. SAVEDATA1000 naming is corroborated by long-running Steam/Nexus backup references.