Report Harassment in Hearthstone

We recommend you don't accept friend requests from strangers.

If someone on your friends list uses inappropriate language or leaves unwanted comments, open your friend list in the Battle.net desktop app, then right-click their username and select Remove Friend. If you want to report them for harassment or for an inappropriate name, right-click the player's name in chat or from the recently played list, click Report Player For, select the most appropriate option, and click Accept.

You can also right-click their portrait in a chat and select Block to prevent further communications.