It becomes apparent he probably ripped these from http://projectpokemon.org/imagedex/ . The way the sprites are organized, and the distance in-between frames are all the same as the shiny overworlds in the image dex.
Comparing the bulbasaur on his sheet(top) to the bulbasaur on Project pokemon(bottom), its pretty obvious.
Comparing the bulbasaur on his sheet(top) to the bulbasaur on Project pokemon(bottom), its pretty obvious.