Here is the video I just made for the Save Abuse x Fossil Conversion crossover to get Mew before your starter, as part of the PRAMA Initiative. Red annotations are in English for international viewer. I couldn't add an English description because of YouTube's limit so I'm posting it here and I will add a link :
[EN] : Video done by Krys3000 of the PRAMA Initiative.
I use the Save Abuse Glitch and the international variation of the Fossil Conversion Glitch discovered by Torchickens/ChickasaurusGL (https://www.youtube.com/watch?v=tEpohfkBg8Q), allowing me to start the game with any Pokemon I want (Mew for this video).
Read the indications before each part of this video (pause the video to read), and turn on annotations. The red ones are for international viewers.
Save abuse is done by turning off the game immediately after saving, when no save file already exists.
It works in Red Blue and Yellow and gives access to 255 glitch Pokemon in the team. I'm only using this glitch here to access to the 33rd Pokemon which is necessary for the Fossil Conversion.
This glitch allows to change the Pokemon that will come out of a fossil. When you switch Pokemon 1 and 33, after you gave a fossil to the scientist, you will get the Pokemon whose decimal value matches with the attack value of your first Pokemon in this list : http://glitchcity.info/biglist.htm
Another used feature of the save abuse is the underflow of the item menu. By changing the quantity of the 36th item, I change the value of RAM address $D365 which controls the ID of the map I'll reach by exiting a building.
The underflow also allows me to get the Dome Fossil, but if you can't find it in your own underflow, you can do that :
- When you are in Cinnabar's Pokemon Center, face the PNJ which allows you to link with another game.
- Switch item 22 (CARD KEY) with item 30 (MASTER BALL).
- Switch item 30 (CARD KEY) with item 36 (MASTER BALL x8).
- Walk 7 steps to the left.
- Switch item 36 (now being DOME FOSSIL) with item 30 again.
- Switch item 30 (DOME FOSSIL) with item 31.
- Go down until you leave the Center, then back inside to continue the glitch as I show in the video.
Here is a summary of the steps :
1. Start the game with save abuse (see above)
2. Switch Pokemon 1 and 10 to trigger the underflow in the item menu.
3. Go to item 36 and toss 248. Exit the house to reach Cinnabar.
4. Go to the PC and store a Dome Fossil.
5. Go on the spot shown in the video, then switch the Fossil to the 36th place. Go one step left to turn it in rare candies, four more steps to turn it into Proteins. Use either or both to get the first Pokemon's attack to 21.
6. Go down to exit the center, then back in to withdraw the Potion then the fossil.
7. Give the fossil to the scientist then switch Pokemon 1 and 33. Go out of the lab, then go talk to him.
8. Go to the Safari Zone by switching Pokemon 3 and 36. Catch a Pokemon, then walk until you don't have steps anymore.
9. Switch 8 - 10 then 10 - 11 to bring the dex to 0 and trigger underflow again.
10. Toss all but one unit of the 36th item and exit the building to warp to Viridian.
11. Change the active PC box and store every Pokemon but one. Withdraw Mew then store the last one.
12. Go get the Potion to the NPC on Route 1, then to Oak to get your starter ! If your item menu is not fixed, getting Oak's Parcel will.