I have recently started playing a local server with a few friends. We have been doing ok, and at the moment, I am the only one who hasn't lost my gear, multiple times, due to either lag or inexperience.
We are getting to the point now where we have access to a couple of Bosses, initially, the Wither, but I don't want people to feel like they won't be helpful, due to their previous track record. So, I wanted to use command blocks to detect if a player is (however many blocks) away from a "Boss Mob", i.e. a mob that has an on-screen health bar.
Is this possible, or do I have to specifically state the Mob in the command?