On Pokémon Black and White there is a Level 70 Volcarona at the Relic Castle but you can only get it after beating Ghetsis. On Black 2 and White 2 you can get a Volcarona at Level 35 after beating the Driftveil gym leader and doing some PWT stuff. It's at the relic castle, but you can only get there by going through the relic pass near the PWT place. Be prepared to catch it (if you're planning too).
So... did you use it?