17 Sonic's Final Boss - Unknown Author Castlevania II & III remix / mashup

Can you ID the source of this Castlevania remix for me? I’d like to know where this came from so I can find it again if it got lost, and see some of the author's other stuff!

The man who gave it to me said it was a track on a disk someone else gave to him, and its title was “17 Sonic’s Final Boss.” Neither remembers where the disc came from, and the disc has since gone missing. I only recently discovered it was heavily based on songs from Castlevania II and III, TYL: That was a big clue.

Here’s some links to OST songs that it appears to have been based on:

Castlevania II
0:00 Bloody Tears (Day theme) - https://www.youtube.com/watch?v=e2oZtvjg5oA&t=0s

Castlevania III
0:15 Beginning - https://www.youtube.com/watch?v=78706bv98S8&t=0s
0:25 Stream (partial chord similarity only) - https://www.youtube.com/watch?v=FpIQt5qUHDk&t=0s
1:53 Riddle - https://www.youtube.com/watch?v=gNOdxV0kAWw&t=21s

Find if you can, and enjoy!
S.D.G.