Download Stone Clones ROM Hack

Application instructions:
Apply to a clean ROM, though really you could apply this to a hack in progress provided the following offsets aren't in use: 0x9C0B22, 0x9D0000, and 0xDB2F5E.  The Hack Addendum patch is meant for my own Emerald Hacks: Pokemon Emerald Hoenn Dex and National Dex editions.  Don't apply this otherwise, it might eat your lunch.

This hack makes up four new evolution stones for trade evolving Pokemon.  Copies of the already existing items Ruby, Sapphire, Dragon Scale, and Up-Grade are made using already and/or dummied out existing data, meaning no free space is used outside of relevant ASM modifications.  The ?real? items have been effectively dummied out, though they still exist (only Dragon Scales and Up-Grades are relevant here anyway, and only Dragon Scale could be found in-game).  There is a version for a clean Emerald ROM, and one for both of my Emerald hacks that uses decapped item names and modifications made exclusively for it.

Ruby:
Machoke>Machamp
Graveler>Golem
Onix>Steelix
Scyther>Scizor
Clamperl>Gorebyss

Sapphire:
Kadabra>Alakazam
Haunter>Gengar
Slowpoke>Slowking
Poliwhirl>Politoed
Clamperl>Huntail

Dragon Scale:
Seadra>Kingdra
Feebas>Milotic

Up-Grade:
Porygon>Porygon2

-Horsea, Seadra, and Kingdra's hold items were changed to the clones of Dragon Scale.

-Wild Feebas and Milotic may hold Dragon Scale, wild Porygon/Porygon 2 may hold Up-Grade (same probability as Horsea/Seadra/Kingdra)

-Wild Lunatones now can hold either Moon Stones or Sapphires, wild Solrocks can hold Sun Stones or Rubies.

-Rubies and Sapphires are sold at Sootopolis City's PokeMart, and it has been repointed to 0x9D0000.
-Addendum only: Names are decapitalized.  Rubies, Sapphires, Up-Grades, and Dragon Scales are sold in the Battle Frontier PokeMart by the Berry shop.

FAQ:
Q: Why two stones for general evolution?
A: As opposed to Fire Red 251 where I only made the Evo Kit there are more Pokemon involved that need changed evolutions.  There is also Clamperl, who has two evolutions that needed to be fixed.

Q: Why Feebas?
A: Same reason as in my own hacks.  Though Milotic isn't a trade required evolution, most of what revolves around it is helped greatly with a Link Cable.  Also, in later games there is an item that is mostly a recolored Dragon Scale specifically to skirt the absence of contests.

Q: Why clones?  Why not make your own stones?
A: I did this for hacks in progress; it lessens the impact on already existing items, and therefore should minimize screwups to modified items.  You can change the properties in any item editor if needed.

Q: Why only Dragon Scale and Up-Grade?  Where's my King's Rock or DeepSea items?
A: Dragon Scale and Up-Grade are the only items that act only as evolution aids.  King's Rock, Metal Coat, DeepSeaScale, and DeepSeaTooth all have a second use, and the method currently used for turning these into stones would rid them of that function.

Item Indexes for XSE:
Dragon Scale>0x59
Up-Grade>0x5A
Ruby>0x5B
Sapphire>0x5C

Tools used:
G3T
Complete Item Editor
Advance Map
XSE

You may use this in your hack, no problem at all!