Order of the Sinking Star Achievements Guide

Use the 18 public conditions below as your checklist. Steam also shows 14 hidden entries without published triggers, so track those as you play instead of guessing from their names.

Follow these 18 public conditions

Steam currently reports 32 achievements for the game. The official achievement page shows condition text for 18 entries. The table uses Steam’s current condition text. Follow the stated milestone exactly; do not treat an achievement name or ID as an extra requirement.

Achievement	Public Steam condition
Heroes	Finish the initial Heroes campaign.
Mirror Isles	Finish the initial Mirror Isles campaign.
Gold HxM	Open the HxM gold room.
Beamcasters	Finish the initial Beamcasters campaign.
Skipping Stones	Finish the initial Skipping Stones campaign.
Gold HxB	Open the HxB gold room.
Antipode HxM	Activate the HxM teleporter to the Antipode.
Gold HxS	Open the HxS gold room.
Gold MxB	Open the MxB gold room.
Gold SxB	Open the SxB gold room.
Gold MxS	Open the MxS gold room.
Antipode HxB	Activate the HxB teleporter to the Antipode.
Antipode MxB	Activate the MxB teleporter to the Antipode.
Antipode SxB	Activate the SxB teleporter to the Antipode.
Antipode MxS	Activate the MxS teleporter to the Antipode.
Antipode HxS	Activate the HxS teleporter to the Antipode.
Endgame	Complete the Endgame.
Completionist	Finish every puzzle in the overworld.

Group the conditions by what you need to do

World codes: H = Heroes, M = Mirror Isles, S = Skipping Stones, and B = Beamcasters. For example, HxM means the Heroes–Mirror Isles pair.

• Campaign: finish the named initial campaign.
• Gold: match the two-world pair, then open that named Gold Room. Steam lists the six pairs but no additional prerequisite puzzle list.
• Antipode: activate the exact paired-world teleporter shown in the condition.
• Endgame: complete the Endgame.
• Completionist: finish every puzzle in the overworld.

How to use the public conditions

If a campaign achievement does not unlock, compare Steam’s exact campaign label with the world you finished. The wording says “finish the initial” campaign; it does not list every internal completion flag or optional room.

The six Gold entries use paired abbreviations: HxM, HxB, HxS, MxB, MxS, and SxB. Match the pair printed in Steam to the same Gold Room in your game, then open it. Steam does not list separate prerequisite puzzles for these entries.

For each Antipode entry, match the exact world pair and activate that pair’s teleporter to the Antipode. Check the Steam label before choosing a teleporter so you do not swap one abbreviation for another.

Steam gives no room-by-room checklist for either goal, so use the exact milestone above as the completion target.

The 14 hidden entries remain a documented gap

Steam also shows these 14 hidden entries: Ascend, High Heroes, High Mirrors, High Skipping Stones, High Beamcasters, Low HxM, Low HxS, Low HxB, Low MxS, Low MxB, Low SxB, Descend, Endgame High, and Endgame Low. Their conditions are not displayed. A name cannot tell you which room, order, or action caused one to unlock.

Use this workflow for a hidden achievement:

1. Keep Steam Overlay or the in-game achievement view available while completing a new campaign or crossover milestone.
2. Record the exact room, world pair, teleporter, or endgame event that preceded the unlock.
3. Wait for Steam to sync, then refresh the achievement page.
4. Treat a community interpretation as a lead until the condition is visible in the game or an official Steam surface.

If one still does not unlock, record the room, world pair, teleporter, or event immediately before it. Use the map and areas guide to identify routes and the hero, mirror, and light guide for crossover mechanics.