You can only get it in the versions ruby, saphire, and emarald.
In order to unlock Rayquaza in SoulSilver, you need to obtain the Red Orb in from Mr. Pok
your main goal is to get all pokemon
You can only get a rayquaza by transferring it from heartgold or soulsilver or by the GTS.
You need to have both Kyogre and Groudon.
You cannot catch Rayquaza in Pokemon Pearl. You will have to have caught it on Ruby/Sapphire/Emerald and migrated it to Pearl. Then you have to catch it at Pal Park.you cant catch rayquaza in pearl. you can only migrate from ruby,sapphire,or emerald or use cheat with action replay. you have to migrate it from ether Pokemon rudy/sapphire or emerald To get a Rayquaza in Pokemon Pearl you will need to trade with Pokemon HeartGold or SoulSilver. To access Rayquaza in Pokemon HeartGold or SoulSilver you need to show Professor Oak a Kyorge and Groudon. This will give the player a Jade Orb that can be used at the Embedded Tower to access Rayquaza in Pokemon HeartGold and SoulSilver. This Rayquaza can be captured and then traded to Pokemon Pearl.
Groudon and Rayquaza are located in the Hidden Tower off of Route 47.
Pokemon Ruby, Sapphire, Emerald, SoulSilver, HeartGold.
I believe the Pokemon would be Rayquaza.
You can only get it by migrating from emerald or trade from soulsilver or heartgold.
After you catch him, you should go to professor oak.
You can always catch Groudon. And Rayquaza too.
The cool legendaries you can get in Soulsilver/heartgold are the following: Lugia, Ho-oh, Raikou, Entei, Suicune, Articuno, Moltres, Zapdos, Mewtwo, Latias, Latios (Latios in Soulsilver & Latias in Heartgold), Kyogre, Groudon, Rayquaza (Kyogre in Heartgold, Groudon in Soulsilver & Rayquaza if you have both).