These are the reports where Ansem recorded his findings about the Heartless. Here are all the locations along with the exact content of each one.
Ansem Report 01 - Defeat Jafar (Genie) in Agrabah
Much of my life has been dedicated to the pursuit of knowledge. That knowledge has guarded this world well. Not a soul doubts that I am blessed with my people's smiles and respect. But though I am called a sage, there are things I do not understand. I believe darkness sleeps in every heart no matter how pure. Given the chance, the smallest drop can spread and swallow the heart. I witnessed it many times.
Darkness... Darkness of the heart. How is it born? How does it come to affect us? As a ruler of this world I must find the answers. I must find them before the world is lost to those taken by darkness.
Ansem Report 02 - Receive from Aerith at the Hollow Bastion Library
It is my duty to expose what this darkness really is. I shall conduct the following experiments:
-Extract the darkness from a person's heart.
-Cultivate darkness in a pure heart.
-Both suppress and amplify the darkness within.
The experiments caused the test subject's heart to collapse, including those of the most stalwart. How fragile our hearts are! My treatments produced no signs of recovery. I confined those who had completely lost their hearts beneath the castle.
Sometime later, I went below and was greeted by the strangest sight. Creatures that seemed born from darkness... What are they? Are they truly sentient beings? Could they be the shadows of those who lost their hearts in my experiments?
Ansem Report 03 - Defeat Ursula's second form in Atlantica
The shadows that crawl beneath the castle... Are they the people who lost their hearts, or incarnations of darkness? Or something entirely beyond imagination?
All my knowledge has provided no answer. One thing I'm sure of is that they are entirely devoid of emotion. Perhaps further study will unlock the| mysteries of the heart.
Fortunately, there is no shortage of test samples. They are multiplying underground even as I write this report. They still need a name. Those who lack hearts... I will call them the Heartless.
Ansem Report 04 - Receive from Aerith at the Hollow Bastion Library
The Heartless appear in groups and are multiplying rapidly. I've provided them with both living and non-living samples. They've responded only to the living. They seem to multiply after absorbing something from the living creatures. Their prey vanishes without a trace.
I believe the Heartless are taking hearts. They are born from those who've lost their hearts and thrive on hearts seized from others. The hearts taken by the Heartless become Heartless themselves.
Though I lack proof, I'm confident in this hypothesis. I must also study their behavioral principles. Though they lack emotions, they do seem to have some intelligence. How to communicate with them?
Ansem Report 05 - Defeat Maleficent (human) in Hollow Bastion
To study Heartless behavior, I picked one out for observation. It wiggled its antennae and as if sensing a target, headed deep into the castle. In the deepest part of the castle, its antennae began vibrating as if searching for something. Suddenly a strange door appeared. I'd never known of its existence.
It had a large keyhole, but didn't seem to be locked. So I opened the door. What I saw on the other side mystified me. What was that powerful mass of energy? That night I observed a great meteor shower in the sky. Could it be related to the door that I have opened?
Ansem Report 06 - Receive from Aerith at the Hollow Bastion Library
A massive core of energy lay beyond the door sought by the Heartless. It may well be the ultimate goal of all Heartless. But what is that energy? I have devised a hypothesis, based upon my observations of the Heartless.
The Heartless feed on others' hearts and they yearn for that energy core. That thing beyond the door must be a heart too -- the heart of this world. There is no proof, but having felt that immense energy I am certain. That |was the heart of the world.
The heartless are trying to take hearts not only from living creatures, but from the world itself. But what do they mean to do with the heart of the world?
Ansem Report 07 - Defeat Oogie Boogie in Halloween Town
I am now studying materials from the meteors that rained down that fateful night. What a find! The material is foreign from our world. It's elastic to the touch and when two pieces are combined they bond easily. None of the records I've scoured even mention such a substance.
Was it introduced to this world when I opened that door? I wonder how many other such material drift through the atmosphere of this tiny world. I wish I could soar off and find out! Could there be uncharted worlds up there? My curiosity never ceases to grow.
But I should stop speaking of such unrealistic dreams. For now there is no way to venture outside this world. My people and I are all but prisoners of this tiny place.
Ansem Report 08 - Defeat Hades in Hades Cup
There is no doubt that the Heartless are deeply connected to people's hearts. Further study may unravel both their motivations and the mysteries shrouding the heart.
As a start I built a device that artificially creates Heartless. By recreating the conditions that spawn the Heartless naturally, I should be able to produce them artificially. This device is the culmination of all my research thus far. The machine's test run successfully created a Heartless.
This may be a step towards creating a heart from nothing. The artificially and naturally created Heartless showed nearly identical traits. But the two types should remain distinct for the purpose of this experiment. So I will mark those that are created artificially.
Ansem Report 09 - Defeat Captain Hook in Neverland
Simply astonishing! Today I had a guest from another world. He is a king and, his vessel is built of the material that composed the meteors. He called the pieces "gummi blocks". It seems that my opening that door has opened a path to interworld travel.
We talked for countless hours but one story in particular caught my interest, that of a key called the "keyblade". The keyblade is said to hold phenomenal power.
One legend says its wielder saved the world, while another says he wrought chaos and ruin upon it. I must know what this keyblade is. A key opens doors. It must be connected to the door that I have opened.
Ansem Report 10 - Receive from Aerith at the Hollow Bastion Library
Just as people have hearts, so do worlds. The same can be said of the stars in the night sky. And deep within each world lies a door to its heart. The Heartless desire those hearts. Born out of the darkness in people's hearts, they seek to return to a greater heart.
Yes that's it. The Heartless come from people's hearts as does the darkness. Is the core of the world's heart the world of the Heartless? I will pursue the answer there and become all-knowing.
My path is set. I shall seek out the wielder of the keyblade and the princesses. My body is too frail for such a journey but I must do this. I will cast it off and plunge into the depths of the darkness.