Pokemon
¤ Red and Blue
¤ Red and Green (Japanese)
¤ Blue Version (Japanese)
¤ Yellow Version
¤ Gold and Silver
¤ Crystal Version
¤ Ruby and Sapphire
¤ Emerald Version
¤ FireRed & LeafGreen
¤ Diamond and Pearl
¤ Platinum Version

Universal Information
¤ What is this section?
¤ Breeding Pokemon
¤ Elemental Types
¤ Pokerus Infection
¤ Shiny Pokemon

Affiliates
¤ Amity Square
¤ Dark Eon Hideout
¤ Eevee's Headquarters
¤ Jenviousity
¤ Lugia's Island
¤ Perfect Absolution
¤ Pokemon Inferno
¤ Pokeshore
¤ PokeTech
¤ Pokeuniverse
¤ Pokemon Valley
¤ Sapphire Milotic
¤ The Spriting Shack

You're going to need two Pokemon for this to work. One of them is Relicanth, which can be found in the seaweed right outside of Sootopolis (you'll need to dive.) They are rock-like fish and are of the same rocky color, but aret somewhat difficult to catch.

The next Pokemon you'll need is Wailord, which can be found on Route 129 by fishing. If that doesn't help, then you'll need to catch a wild Wailmer and raise it to Level 40. Best to fish around Mossdeep for those. Now, teach a Pokemon Dig and bring it with you.

Now that you those two, fly or surf to Pacifilog Town. From there, Surf west and stop when you get to the current. Surf down and get the current lane shown in the left screenshot. You'll end up in the same place as the screenshot on the right when you leave the current.

You'll hit more land with a Fighter Trainer on it, and you'll want to keep going to the last rock on this island. Surf at this level until you reach an island with nothing on it. it is past the island that is shaped like a square ring.

When you reach the island (like the one in the last picture) you'll want to count three spaces up from the bottom. This is where you will want to Surf from. When you stop, you'll reach a small pool that you can Dive. Preceed to do so. Under the water, you'll want to leave the underwater room and head for the end of the underwater hall. At the end will be some writing on the wall. Press A, then Dive. You'll land inside a cave.

Go to the back of the room, read the wall and use Dig. The wall will turn into a hole: Go on in. Now, place Recalith in the first battle slot and Wailord in the last battle spot. Go to the back of this room and read the wall. After you get done, the screen will shake and three doors can be heard opening. Now Dig, or use an Escape Rope to leave here easily.

Before you set out on your quest to find these Pokemon, you'll want to have Pokemon that know Strength and Fly. Stock up on Ultra Balls (as many as possible), Timer Balls, and restorative items.

The easiest way to catch them is the put them to sleep when they are in the red or dark orange area. Throw Ultra Balls until you catch it, and throw Timer Balls when you've thrown 20 or more Ultra Balls. With a little luck, this will catch all three.