Capture The Three Legendary Regis:

you will need: wailord, relicanth, surf, dive, fly, strength, dig

1.go to pacifidllog and surf west. you encounter some dangerous currents so stick to the bottom of the screen for a while
2. find an area of deep water (not the one surrounded by rocks, even if you have walk through walls on it will not take you anywhere) and dive down.
3. you are now swimming down an underwater tunnel (i don't get it, why don't you run out of air?) so keep going until you reach the area where theres dots on the wall. it is actually a braille code and if you can't be stuffed to look up what it means, it says: GO UP HERE. so, facing the dots, resurface.
4. you will find a large room with the braille alphabet etched on large boulders. continue to the end of the cave, where it says: DIG HERE. so use dig.
5. it is really cool to read what these small six or so tablets say but they don't do anything. so go to the very end of the passage and you see written in braille: FIRST COMES RELICANTH, LAST COMES WAILORD

so you have to have relicanth first in your party and wailord last. you hear three distant clicks. like some doors have been opened.

now you have unlocked them, you can go to the rocks where they are hidden in.

for regice:
go to dewford and surf north-west. you should encounter a ruin maniac on an island. if you do, your on the right track. surf a little further north-west and you encounter a large rock surrounded by six smaller rocks. the large rock now has a cave entrance. go inside and you find another braille code. it says: STOP AND WAIT. WAIT FOR TIME TO PASS TWICE. or something along the lines of that. so, just leave your GBA on and wait for like two minutes, just be patient. the cave opens and you can enter in to battle regice.

for registeel:
go to fortree and go east, then south. keep going until you're past the rainy feild of very tall grass and go LEFT, then go up when you see berry bushes and a random person walking randomly next to them. keep going past the water and into the patch of tall grass past the ninja who is hiding behind a piece of cardboard. then it starts raining. there is a ruin maniac here too! well, now the large rock surrounded by six smaller rocks is open, you can enter into it.
the braille says: WITH NEW TIME, HOPE AND LOVE, AIM TO THE SKY IN THE MIDDLE. so go to the center of the cavern and use fly. the cave opens and you can enter in to find registeel.

for regirock:
go to the sandstorm place the ruin maniac is running tirelessly around a rock to the south. now go down as far as you can. you will find a large rock with six smaller rocks surrounding it (like the others). now enter. the braille says, RIGHT, RIGHT, DOWN, DOWN, THEN USE STRENGTH.
so go right two spaces, the down two spaces and use strength.

these pokemon are ultra-powerful, so come prepared for a tough battle!