Level up with AncientPower...Doubtful. They don't evolve old Pokemon by methods that are available in previous generations... Maybe it evolves after spending time in the Dream World?
Regarding ability: GameFreak tend sto be philsophical sometimes. So I'd suggest "Guts" or "No Guard". =)
Which we don't no much about, great. lolluvdisc evo confirmed to have the ability セクシーなドライブ rumored to act the same way as Reshiram and Zekrom's turboblaze and terravoltage