I'm not expecting you to reveal your secrets but just... how does anyone get a collection like that? And when did you start fetching them?
I sincerely though most of those games were just long lost.
A while ago Neopets had a glitch that made their site open directory. This meant if you went to images.neopets.com/games/ you could see every file in that folder.
I know that's how my archive of sponsor games was passed down to me, I obviously can't speak for Bat.