The pre-OP scene does not match the OP at all. Change it already!
It's crazy to see Killua's family be on equal ground with Chrollo in a fight like that, even having the upper hand and putting him on the defensive. And the preview shows all kinds of things that I'm very curious to see.
Avatar: Tomoya Okazaki from Clannad/Clannad After Story (courtesy of Jun Kuga/Fudce from The Fandom Post)