Complete playthrough and achievement guide. Includes both a full video playthrough and descriptions on how to unlock all achievements.
 
 

Introduction and Full Playthrough

Abyss of Neptune is an impressive free underwater horror game.
 
 
A full video playthrough showing how to complete the game from start to end will appear here shortly. It will contain references and timestamps on where the achievements will unlock.
 
 
 

Abyss of Learning

Complete the tutorial.

 
This is story related and will be unlocked as soon as you enter the first hallway.
 
 
 

Abyss of Shooting

Get the harpoon gun.

 
This is considered story based and is obtained by progressing through the game. However for reference, it’ll be lay on a table in the Kitchen.
 
 
 

Abyss of Searching

Find 3 logs.

 
See below under Abyss of Completion for a full set of locations. However, you should easily find 3 before leaving the first area of the game.
 
 
 

Abyss of Exploration

Find 6 logs.

 
See below under Abyss of Completion for a full set of locations. However, you should have 6 logs before leaving the second area of the game.
 
 
 

Abyss of Academia

Complete the Academics Wing.

 
Story based and will be unlocked as you progress through the game and enter the final area.
 
 
 

Abyss of Completion

Find all logs and complete the game.

 
There a total of 10 Logs to find throughout the game.
 
 
Log 1: “IT’S KILLING US”
 
Location: Access Hallway – Near the beginning of the game, you’ll eventually come to a stairway that leads you into the main compound. Under this stairway is the first log.
 
 

 
 

 
 
Log 2: “The Reefs Are Back”
 
Location: Cafeteria – In the far corner on the floor against a set of unturned tables.
 
 

 
 
Log 3: “WE DID IT!”
 
Location: F Showers – Travel through the air duct in the ceiling from the M Dorms room. The log is on the floor in the cubical missing a door.
 
 

 
 

 
 
Log 4: “Neptune”
 
Location: Lobby – In the middle of room hidden amongst a pile of chairs and tables.
 
 

 
 
Log 5: “Failed Rituals”
 
Location: Librarian’s Office – Hidden to the right of doorway as you enter.
 
 

 
 
Log 6: “I know what we’re missing”
 
Location: Control Room – Against a table locked inside a box. Use your key to unlock.
 
 

 
 
Log 7: “We’re Close”
 
Location: Hallway (1F) – Enter the duct from Hallway (2F) and follow it through all the way to the exit at Hallway (1F). The log is at the very end of this tunnel next to a medkit.
 
 

 
 
Log 8: “The f**k are you doing down there?”
 
Location: Atrium (1F) – Sitting in an open part of the plant life on the very top platform of this circular room.
 
 

 
 
Log 9: “Adam”
 
Location: Historical Records – As you enter, stay to the righthand side of the room and follow it all the way to the back of the room. The log will be at the very end where it becomes blocked underneath a “G – Z” sign.
 
 

 
 
Log 10: “I’m so tired”
 
Location: Intersection – After taking the elevator down, find the duct entrance on the floor in this room. The log and medkit should be visible as soon as you enter.
 
 

 
 

 
 
NOTE: The achievement will only unlock once you complete the game.
 
 
 

Abyss of Developers (Secret)

Find the hidden room.

 
 
You can only reach this hidden room once you’ve taken the elevator down to the last part of the game, before you take on the final boss. In this room you will find a locked safe which will contain a 10V battery to help you unlock this achievement.
 
 

 
 
At numerous times throughout the game you have encountered rooms that hold a counter where you can swap these batteries to unlock various sections of the map. The hidden room can only be entered from the Kitchen which is at the beginning of the game! So yeah, we need to head all the way back and swap out a batteries along with way.
 
 
So once you’ve retrieved the battery, head back up the elevator and towards the Control Room. Ensure you have 15V active on this counter before moving on.
 
 

 
 
Now head back to the Kitchen and ensure you have 20V active on this counter to unlock the Air Flow in the duct behind you on the floor.
 
 

 
 
Now enter the duct which you should now be able to navigate freely. Travel all the way to the end to finally get to the secret developer room.
 
 
 

Abyss of Mercy

Complete the game in easy mode.

 
Nothing more to add as the title says it all really 🙂
 
 
NOTE: This achievement will unlock if you complete the game on normal mode.
 
 
 

Abyss of Persistence

Complete the game in normal mode.

 
See above.
 
 
 

Abyss of Grit

Complete the game without using any healing items.

 
Not as difficult as you may think as long as you’re careful to dodge, run and shoot when necessary. You can take 4 hits from any enemy which ultimately means you have 4 lives to play with. Also remember you can retrieve any misfired harpoons.
 
 
 

Abyss of Speedrunning

Complete the game in under 30 minutes.

 
Again, not overly difficult once you know the layout of the map and object placement. The only time this becomes an issue is in the latter third of the game when you face the larger creature. It does spawn randomly around the map which can cause you to get side tracked, eating precious time.
 
 
 

Final Thoughts

 
 
I hope you enjoy the Complete playthrough and achievement guide – Abyss of Neptune guide. This is all for now! If you have something to add to this guide or forget to add some information, please let us know via comment! We check each comment manually!