sure can
you cant unless you trade from Pokemon colosseum sorry!!!!!!!!!!!!!!!!!!
you have to trade him from Pokemon ruby or emerald.
No but you can get Lugia in Pokemon Xd just trade it to a GBA Pokemon version like Ruby then trade it to colosseum.
You would have to trade a groudon from ruby or emerald to colosseum to have one.
You cannot trade Pokemon to Pokemon Colosseum, but you can trade the Lugia you catch to Ruby or Sapphire.
Catching Celebi in PokemonTo get CELEBI in CRYSTAL VERSION I heard that you have to catch all 26 different UNOWN. Then Put the following UNOWN in you party in this order(From top to bottom). UNOWN C, UNOWN E, UNOWN L, UNOWN E, UNWON B, and UNOWN I. Then go to the shrine in ILEX FOREST and click on it. NOTE: This might not work because it says you need two UNOWN E.
You can trade with another sapphire, ruby, emerald, firered, leafgreen, Pokemon colosseum, Pokemon xd gale of darkness and Pokemon box ruby and sapphire.
You have to trade from Pokemon XD or Ruby, Sapphire, Emerald, Leafgreen, or Firered.
No you cant catch Latios in Pokemon Colosseum. You can only trade it in from your Ruby or Sapphire game in to the Colosseum game and that's the only way you can get it.
I don't believe you can get Celebi on Ruby.
I'm going to assume you mean "Pokemon Ruby" in your question. Anyway, to trade between Ruby and XD, you must beat Pokemon XD and defeat the champion in Ruby.
You cannot catch/see 'Entei' in Pokemon Ruby. The only way to get it to Ruby is to trade it from Leaf Greean, Fire Red or Colosseum.