I've talked to Wallace in the cave of Origion,a nd I told him I though that rayquanza was in the Sky Pillar.
But I don't know how to get to the Sky Pillar.
Its really giving me a hard time.
2) Surf east. Before you get there, you should see a swimmer and a dougle battle.
3) Keep going east (right) until you ght a random clump of rocks. (Not a row of rocks, but a clump of about 25 of them.
4) Go up the right side of the clump (there will be a small opening)
5) Continue following until you hit sand.
6) Enter the building opening and follow the cave up, left, then down.
7) Wallace will come to you and ramble on about Sky pillar.
8) Go up the pillar and press "A" on Rayquaza.
9) It'll fly to sootopolis and clear upo the Kyogre/Groudon Battle.
10) It will then return to Sky pillar.
11) Go get a Mach Bike from Mauville in rydel's bikes.(IF you arleady have a mach bike, go next step)
12)Return to Pacifidlog with at least 50 ultra balls, a few timer balls, and a pokemon that can withstand level 75 beatings. Or a master ball.
13) Ride up the pillar, while using the mach bike at top speed to go over the cracks. You dont have to go over all of them. If you stay on a crack for too long, you will fall down.
15) Catch Rayquaza.
16) Go beat the E4!
Glad I could help.