If you are chasing Back Off Man. I’m a Scientist, the real enemy is not the ghosts. It is missing one scan during a noisy checkpoint and not realizing it until much later.
This page follows the realistic / HD campaign order for the PC, PlayStation 3, Xbox 360, and remastered story branch. It is built as a cleanup companion, not a lore dump, so the focus stays on what to scan, roughly when it appears, and what players tend to miss.
Quick guide links
- Unlockables and Supplemental Data for the broader cleanup section.
- Realistic / HD Campaign / Walkthrough if you want the full room-by-room mission route beside these scan notes.
- Tobin’s Spirit Guide if you need to cross-check what an entry is called after you log it.
- Cursed Artifacts and Water Fountain Locations if you are bundling collectible cleanup together.
- Boss Fights for the faster stuck-player version of the major showdowns.
How to use this page without wasting a replay
- Grab the scan the first clean moment a new enemy appears. Do not assume you will get a calmer second chance.
- If the Spirit Guide entry only shows the basic name and picture later, the game probably recorded the sighting but not a full scan. Re-run that checkpoint and rescan it properly.
- The level-select career screen is your friend. It shows how many ghosts and artifacts you have found in each chapter.
- By the late game, some hazards and black-slime entries should already be in your book. The list below still calls out the genuinely new scans so you do not overthink the final cleanup.
Scan route by chapter
Welcome to the Sedgewick Hotel
- Bellhop Ghost – right when the ghost staff rushes in during Bad Service.
- Dead Fish Flier – in the sealed kitchen stretch during Air in Line.
- Slimer – automatic boss encounter in Rodriguez Bar Mitzvah; do not forget to stop and scan before the chase gets silly.
- Candelabrum Crawler – after the flooding starts during Charge of the Light Brigade.
- Pappy Sargassi – boss fight at Sargassi’s by the Sea.
- Kitchen Golem – boss reveal in And the Kitchen Sink, Too.
Panic in Times Square
- Marshmallow Mini – early in Mass Panic while following Ecto-1.
- Hobo Ghost – right after the Marshmallow Minis in that same opening push.
- Stone Gargoyle – after the cutscene in Ghosts and Gargoyles.
- Construction Worker Ghost – once the Gargoyle wave settles.
- Opera Diva Ghost – during Hindenburg: The Musical after the black-slime lead-in.
- Stay Puft Marshmallow Man – late in Shadow of Stay Puft; scan him as soon as he gets close enough instead of waiting for a prettier moment.
Checking Out the Library
- Cruster and Book Golem – both arrive early in Dangerous Books.
- Librarian Ghost – follow the P.K.E. cue at the start of Ssshhed Again.
- Book Bat and Crusto – both show up during the next enclosed library fights.
- Paper Construct – in Slippery when the ambush triggers near Ray.
- Book Centurion – toward the back of the room in Special Collections.
- Coal Golem – down the stairs in The Trouble with Golems.
- Cultist – in Hall of Mirrors.
- Azetlor the Destroyer – at the start of Wrath of the Collector; easy to get if you remember to do it immediately.
Museum of (Super)Natural History
- Possessed Human and Possessor Ghost – both come out of the early Rutherford rescue sequence.
- Beauty Queen Ghost – slime the possessed target during Opening Night so the ghost pops free for the scan.
- Possessed Statue, The Chairman, and Flying Skull – all arrive during the Chairman chase block.
- Union Ghost and Confederate Ghost – scan one from each side when the Civil War battle kicks off.
- Venom Crawler, Black Slime Fiend, and Black Slime Ghost – all show up during the deeper Chairman material, so do not leave that stretch thinking it was just one fight.
Return to the Sedgewick
- Webbed Fiend – near the main entrance during Enter the Spiderwitch.
- Cook Ghost, Chef DeForrest, and Kitchen Flier – all belong to the kitchen cleanup in Power Restored.
- Spider Crawler – on the way through Ghostworld Again.
- Spiderwitch – at the end of Lair of the Spiderwitch.
Lost Island Rising
- Black Slime Monster – after draining slime in Black Slime What!?.
- Imprisoned Juvenile Slor – in Black Slime Beast once you break the orbs and the real boss emerges.
- This late in the campaign, the guide source assumes you already have several common black-slime and hazard entries logged. These two are the important truly new ones.
Central Park Cemetery
- Cemetery Crawler – shortly after the first gate controls.
- Grave Fiend and Cultist Summoner – during the boneyard fights.
- Grave Monster – during the return-key stretch in Crypt Alley.
- Stone Angel – at the start of Attack of the Stone Angels.
- Keyhead Monster – immediately in Headstones.
- Shandor the Architect – in the final sequence, as soon as you are close enough for a clean scan.
- Like Lost Island, this chapter assumes your running hazard scans are already in place.
Other entries you should already have
- Sloth Ghost is effectively handled for you at the beginning of the game before proper scanning opens up.
- Black Slime, Black Slime Portal, Ectoplasm, and Ectoplasmic Residue are recurring field entries rather than one-off boss catches.
If the trophy or achievement still will not pop
- Open the Spirit Guide and look for entries that still show only the bare name and image.
- Replay the most likely checkpoint and rescan that target dead center.
- If you are also doing collectible cleanup, keep Cursed Artifacts and Water Fountain Locations open beside the level hub so one replay can solve multiple problems.