I need to beat the elite four and I need to know a couple of things?

You are pretty good. All you need to rise the other pokemon about level 48 through 50 ish. I used a lot of health items also after battles to make sure the next elite four member not knock me out. They ar pychic, dark, fighting, and ghost type members. I bet you have white then. The final battle has level 54 for the highest and it is hydreigon, the most ugly looking pokemon out there. It is a dark dragon type. Evolve the sandile into a krookodile. I use it in the elite four. If you still have the rage candy bar, feed it to one of the statues in the dessert to catch a strong fire type pokemon called darmanitan. It has the ability zen mode to increase sp defensive, defense, sp attack, and lowers attack plus speed. It is in that mode when it is half health. Try to get a scolipede that has the moves venoshock, baton p, iron defense, and steam roller. It is quite destructive if it has the item rocky helmet and the ability poison point. Venoshock causes twice the damage if the enemy is poisoned.