Description
Red & Blue MissingNo, MissingNo Fossil Aerodactyl, Kabutops and Ghost Form GlitchesThe Aerodactyl and Kabutops Fossil Forms Glitch
So this is similar to the MissingNo Glitch because the Pokemon behind The Fossil form Aerodactyl and Kabutops is actually Missigno but Fossil Aerodactyl Form.
So to get Fossil Aerodactyl do this following steps:
1) Have 7 Badges
2) Talk to the man that teaches you how to catch Pokemon
3) Have a w in second, forth and sixth slots of your name.
4) Go to Cinnabar Island
5) Surf on the eastern coast of the island
The Aerodacyl Fossil Form should show up.