Help in pokemon Heartgold beating the elite four-rematch?

Possible. Lance's pokemon are sickenly powerful this time. No matter how hard you hit them they will survive, no matter how fast your team his are faster and no matter how good your defenses are every time Lance attacks it will either be a 1HKO or a redline. You need to be in the 80's to even stand a chance. Even my team in the 90's at this point have a hard time without choice items.