Changes from Ruby and Sapphire
• Kyogre and Groudon no longer can be captured at the Cave of Origin. Instead, you will have to awaken Rayquaza in the Cave of Origin after kicking the Magmas and Aquas out of Kyogre and Groudon's preliminary abodes so it can stop the meteorological feud between the two. After you defeat the Pokémon League, Kyogre can be found on the eastern seaboard while Groudon takes up residence in the vicinity of Mount Chimney. Rayquaza can still be caught at Sky Pillar. And for the record, both Kyogre and Groudon's levels have been inflated to 70.
• In Emerald, you decide whether you want to face Latias or Latios. After that news bulletin, your mother will inquire for the colour of the Pokémon. Say 'blue' and you're looking for Latios; say 'red' and you've got yourself a Latias goosechase.
• The Altering Cave that appeared in Fire Red and Leaf Green appears on Route 103.
• Birch gives you the National Pokédex after you defeat the Pokémon League.
• It is now possible to obtain both the Root and Claw Fossils. In the Desert you will find Illusion Pillar; at the top are the two fossils. Select one and the pillar collapses. After you defeat the Pokémon League, go by the Fossil Maniac's house and you should come across a new cave. The fossil that you failed to pick up will be in there.
• You can face the Gym Leaders again after you defeat the Pokémon League.
• Steven has resigned from the post of Champion, leaving it to Wallace. Ardan takes Wallace's place in the Sootopolis Gym.
• Team Magma will appear at the Space Station.
• A new Battle Tower wilol appear to the north of Mauville.
• After you defeat the Pokémon League, the Safari Zone expands to include a larger denomination of Pokémon.
• All of the Contests have been moved to Lilycove City and take place under one roof. Where the old halls were are now Battle Tents, the procedures in which are a little like the ones in Pokémon Stadium 2.
• All Pokémon sprites in battle are animated.
• There are several new tournaments taking place, and they're on an island locale remote to Hoenn.
• Deoxys takes a Speed-optimised form in Emerald.
• Sudowoodo and Smeargle can be caught in the wild.
• Mew can be caught on an island accessible with a ticket.
That's all I have now; I'll submit more as I find out more.
Added by: Cross Stinger Dec 12th 2004, ID#3845