What is the song in Hunter x Hunter (2011) ep. 70 at 19:00?
If you are referring to Hunter x Hunter 2011 Episode 70 titled "Guts × And × Courage" during the dodge ball match, the song you hear around 19:00 seems to be an instrumental version of the ending song Reason by the band Yuzu. If you would like a more complete list of the music used in Hunter x Hunter than can be found here: Comprehensive list of Hunter x Hunter Music.