It's not like we have a choice. We need to find out who killed him and exactly why they decided to make the first move here.

[ What a surprise, though. Killua's almost surprised that it wasn't actually him that'd killed someone first but the reason they wanted them to do it for just wasn't worth it. So the obvious solution left was to find out what - and who - had killed this guy. ]

They gotta have a reason for it.