When u have officially beaten all 8 gyms and have caught Groudon heres what you do. Go to the daycare and put in 2 pokemon (or 1) and do what a lot of people do--- Just go to a mudslide thing and tape down the button so ur just stationary. Now the next step is very difficult. WAIT. Wait as long as you want and come back to see how much theyve grown. I did this twice and got a lvl 89 blaziken lvl 90 groudon lvl 84 camerupt and a lvl 89 Wailord. I fully understand this takes a while (max. 5 days) but i breezed by the E4.