Notes:

Quick observations:

• Vullaby/Mandibuzz doesn't exist in early builds. Same goes for Durant, Bouffalant, Cottonee, Whimsicott, Lilligant.
• Shelmet was supposed to evolve into Escavalier. Karrablast meanwhile had its own evolution.
• Stunfisk is blue because it was originally Water/Electric.
• Scrafty was meant to be in Gen 3 and its evolution was a beta version of Grovyle, but ended up moved to Gen 5.
• In older builds, there was no Zebstrika, but a weird-looking middle stage between the two Zebra mons.
• Early versions of Black and White Kyurem were just a Red and Blue Kyurem.
  *Mons that exist but weren't included in here for some reason:
  • Oshawott's family
  • Haxorus