How do you get all the legendary Pokémon on Pokémon ruby?

Answer 1

All the legends in Ruby are Groudon, Regirock, Regice, and Registeel, Rayquaza, and Latios OR Latias. If you want the others, you'd have to trade with Sapphire or Emerald or use a GameShark... You'll get Groudon as you play through the game's storyline. The Regis cam be found in their own caves. **Prepare for a long guide**

First you need two Pokemon: Relicanth and Wailord. Relicanth can be found in the underwater seaweed around Sootopolis City and you can fish up a wailmer on Route 122 and level it up to 40 to evolve it. And you just need some Pokemon on your team that know Fly, Dig, and Surf~ To be able to go to the actual Regi caves, you need to unlock them by going to Pacifidlog Town, Surfing west and keeping to the bottom of the currents to get to a place you can dive down to. When you reach the divable pool, dive and swim south until you reach some braille on a wall (Go up here), examine it, then resurface~ You'll end up in a room full of braille... just walk to the north of the cave to the middle braille sign (Dig Here). Use Dig and a hold will appear in the wall! Continue into that room and to the middle slate of braille (First comes Relicanth last comes Wailord). Put Relicanth at the top of your party and Wailord as the last poke in your party, then just press A and there should be an earthquake that unlocked the Regi caves!~ For Regice, surf west and north of Dewford town until you come to a big cave surrounded by 6 small boulders in the water. Go inside and up to the braille, examine the braille, and just put down your game and don't touch anything for a little while, after that the door should open to Regice. For Regirock, go to the VERY south of the desert to find the cave. Go inside to the braille, examine it, then walk 2 spaces to the right and 2 spaces down then use Strength; the door should then open and you'll be on your way to Regirock. For Registeel, go east and south of Fortree City to the same type cave and go inside to check the braille. Walk to the center of the room and use Fly to be on your way to the last Regi.

Now for Latias/Latios, that depended on you picking either RED or BLUE when your mom asked you what was on the television at the end of the game. If you picked red, Latias should now to roaming around Hoenn, and if you picked blue, it'll be Latios instead of Latias. Getting your Lati can take a long time... but don't worry~ Find some route that has a patch of grass very close to the entrance/exit. Just go into the route's grass and out of the route a million or so times and your Lati should appear eventually~ If you didn't use your Masterball yet, it'll be REALLY handy for catching the Lati that will flee after 1 turn of the battle. If you HAD already used your masterball, you'll just need to put it to sleep, repeat the searchign process, get a hit in each time your encounter it, and continue searching and encountering until your Ultra Ball works.~

Rayquaza can be found after you beat the game~ Make sure you have the Mach Bike handy and surf east of Pacifidlog town until you come to a cave. Go through the cave and you'll end up at the Sky Pillar. It has several floors- the first few are easy, but they get harder. You need to go over the cracks in the floor really fast on your bike. It might take a few tries to get through. Rayquaza is at level 70, so be prepared~