I don't know why, but I never had an easy time with Charlotte. It tends to take about 5 tries for me to beat her now, yet alone about 6 versions ago
Same with Titania. I had to meticulously counter her Pokemon in order to beat her.
Serra, is all about that hax. Evasion was her game and I did not like it.
Terra's Garchomp. I had no idea why it was doing so much damage to me. I would Intimidate it and drop it's SpA and it would still 2KO if not OHKO me.
Remember when Noel's Cincinno had Skill Link Kings Rock? I used to have a difficult time with that...geh.