Disclaimer: I do not own Kingdom Hearts. It is owned by Tetsuya Nomura.
Flashback:
They came at night. The seven of Ansem the Wise's apprentices came and took many individuals. Those taken were never heard from again. The horrendous experiments the apprentices used to completely eviscerate the captives' hearts to the extreme. The experiments sucked all of the light out of the captives, and the accumulation of the 'patients'' darkness soon snowballed. All of the captured civilians had their hearts collapsed and were transformed into beings of darkness, now known as the Heartless, varied in shape and size. The head apprentice, Xe-ha-nort, had taken one of the altered captives, now what is known as a Shadow, and observed it's behavior, showing an animalistic simplistic mindset. Soon after, Radiant Garden began to disassemble into the darkness, while many who had not been taken captive screamed and panicked with hysteria as they all saw and felt the whole world fall apart. They panicked even more when they perceived the Heartless swarming upon them in droves. This was the beginning of the End of the World, and the start of the chaos that several suffered through.
Authors' Notes:
Jiminy's Journal:
Shadow:
One of the many forms the heart takes after being swallowed by darkness.
Being that appears along with the darkness. It searches for hearts to attack them.