How to report another player that is using an offensive or inappropriate BattleTag
How to report a player for cheating in Diablo III
How to report a player who is threatening with harming another person or a place
How to report players in Diablo III.
How to block communication from another player in Diablo III.
How to block communication from another player in the Battle.net Desktop App.
How to report harassment taking place within Battle.net chat (mobile or desktop)