How to unlock: Examine the cyst in the Vast interior(M16.6) and obtain the Mesmeric handle.
Note - This is a pretty important quest that you ought to do during your first visit in the Interior. In order to finish it, you have to have a certain scalpel that allows to cut Maws within the Bloom. This artifact can also help with exploration of the Bloom.
To unlock this quest go to the Vast Interior. Near the Sundermuns' store, you will find a cyst. Interact with it. Examine it (you will notice there's a creature inside) and the touch it.
The first vision will be triggered, during which you should choose the options that will allow you to examine the memories more thoroughly. Don't choose to end the vision or escape! Finishing the first vision will yield 2 XP. Touch the Cyst again to trigger another vision. In this case, proceed in the same manner - examine the memory. You will get 2 XP. In the last vision choose the options that exhibit your courage. You should get 4 XP.
You don't have to be extra cautious because if you act in the wrong way during one of the memories, you will be able to activate the vision again. Your actions should ultimately cause the Cyst to burst and Abykos to get out of it - he will then escape from the whole Interior (you will be able to meet him again). Examine the remains of the cyst and you will find the Mesmeric handle and a new entry to the journal will be added.
Open the inventory and examine the handle to read the name carved on it: Ioxu. If Ioxu is still alive, you can go to his hut (M16.1) and show him the handle to learn how to craft a special scalpel (a source of energy will be needed).
If Ioxu has been killed (which can happen during the side quest Anathema), the quest can still be completed. The only difference is that you won't have the instruction of finishing the item, so you'll have to figure it out yourself. Or use this guide.
Move to the district of Small Nihilesh and find the entrance to the cathedral in the north-west corner of that place (M19.9). After getting inside, approach the control panel and interact. The source of energy you're looking for can be obtained in two ways:
- Amiably reach a consensus with the ghosts and use Persuasion/Deception and Anamnesis in order to transfer them into the mind of the protagonist. This will allow you to get the thing you're looking for, no problem.
- Ignore the ghosts and focus on extracting the source of energy. This will be possible via passing some skill tests.
Regardless of your decision, you will obtain a Transdimensional Energy Source. You can get back to Ioxu for a moment, or proceed to crafting the item at once. Open the inventory again and examin the handle. Choose the new action and pass the test to successfully combine the two items. You will get 25 XP and a Transdimensional Scalpel. It's a light weapon. Its main application is opening Maws while exploring the Bloom.