In Pewter City Museum, you can see pictures of Kabutops fossil/skeleton and Aerodactyl fossil/skeleton, but none for Omastar. Two Missingno. variants in the first Generation games have these skeletal sprites (the Kabutops one appears awesome). Guess what two fossil Pokemon are revived in Movie 5? And I do recall seeing an early trailer (trailers always lie) in which the two revived fossils remained as skeletons.
I am a glitcher, not a cheater. I do not alter game codes, but use what's given to get what I want.
As an RNGer, I can RNG any breedable and encounter Pokemon to any nature, ability, IV spread, shininess, etc. For those in dire need of a certain Pokemon, I might accept trade requests for any breedable Pokemon to full specifics (DW Abilities limited, ask for availability) in return for 1 Rare Candy.