Why does my game reset progress after a boss fight?

Because the milestone isn't durably saved: there's no save triggered right after the boss (so a crash or quit before the next save point loses it), the save runs but doesn't capture the updated progression state (saving stale data), or a crash during/after the intense boss fight prevents or corrupts the save. Boss fights are high-risk because they're crash-prone moments followed by a progression update.

How do I make sure beating a boss saves?

Trigger a save immediately after the boss is defeated (and other milestones), don't wait for a distant next save point, so the achievement is recorded before anything can go wrong. Verify the save actually captures the updated progression (the boss-defeated flag, unlocks) by testing beat-save-reload. And make the save atomic and robust so a crash right after the boss can't corrupt or skip it.

Why does my save not include the boss I just beat?

Because the save is capturing stale progression state, a bug where the save runs but doesn't include the just-updated data (the boss-defeated flag isn't set yet, or the save reads old state). A save that runs but saves the old state is as bad as no save. Verify, by beating the boss, saving, and reloading, that the new progression is actually in the saved data, and fix the ordering so the save captures the updated state.

How to Fix Progress That Resets After a Boss Fight

Quick answer: When players lose progress specifically after a boss fight (or other milestone), the milestone isn't being durably saved: there's no save/checkpoint triggered after the boss, the save runs but doesn't capture the updated progression state, or a crash during/after the boss prevents or corrupts the save. Add a reliable save immediately after the milestone, ensure it captures the new state, and make it robust so a crash can't cost the player the boss they just beat.

Losing progress right after beating a boss is an especially cruel bug, the player accomplished something significant, often after multiple attempts, and the game throws it away. It points at a specific gap: the milestone wasn't durably saved. Because boss fights and milestones are exactly the moments players most expect to be saved, this bug is both common in impact and clear in cause.

Why Milestones Don't Stick

Progress resetting after a milestone means the milestone state wasn't durably persisted before the reset (a crash, quit, or reload). The gaps: no save after the milestone, the game doesn't trigger a save/checkpoint right after the boss is beaten, so if the player crashes or quits before the next save point, the boss-defeat isn't recorded. Save doesn't capture the new state, a save runs but, due to a bug, doesn't actually include the updated progression (the boss-defeated flag, the unlocked area), so it saves the old state. Or a crash wipes it, the boss fight or its aftermath crashes (or corrupts the save), losing the just-earned progress.

Boss fights are high-risk for this because they're intense moments (more likely to crash) followed by a transition (where progression state updates), and if the save doesn't reliably happen and capture that update, the milestone is lost.

How to Diagnose It

The pattern is specific and reported clearly: players lose the boss/milestone progress, 'I beat the boss but it didn't save' / 'I had to fight the boss again.' Check whether a save is triggered right after the milestone, and whether that save actually captures the updated progression state (test: beat the boss, save, reload, is the boss still defeated?). Also check whether crashes correlate with the boss fight (intense moments crashing, then losing the unsaved progress).

Bugnet captures reports and crashes with context and version, so milestone-loss reports (and any crashes around boss fights) surface, and you can see if a crash near the boss is costing players the save. Because re-fighting a boss is a major frustration (and a refund/review driver), prioritize this even at modest report volume, each instance is a significantly annoyed player.

How to Fix It

Save reliably right after the milestone, and capture the right state. Trigger a save immediately after the boss is defeated (and other significant milestones), so the achievement is recorded before anything can go wrong, don't wait for a distant next save point. Ensure the save captures the updated progression, verify the boss-defeated flag and any unlocks are actually included in the saved data (a save that runs but saves stale state is as bad as no save). Make the save robust, atomic and verified, so a crash during/after the boss can't corrupt or skip it.

Also harden the boss fight and its aftermath against crashes (since a crash there costs the milestone), and consider that the player should never have to repeat a beaten boss due to a save gap. After fixing, verify the test: beat the boss, and via crash, quit, or reload immediately after, confirm the progress sticks every time. Reliable milestone saving respects the player's accomplishment, which is exactly what makes losing it so damaging when it fails.

Losing a beaten boss means the milestone wasn't durably saved. Save right after the milestone, confirm the save captures the new state, and make it crash-proof, never make players re-fight a boss.