[The Rock-man]

Your talking about undead bosses in your post.

It a support mastery as I said before it really needs another mastery with it to get the most out of it, compared to a lot of the others that can stand alone fairly well.

Archery, Close Combat, Sorcery & Bestiary are clear cut primaries.

Primaries/Secondary hybrids are IMO all the rest of the masteries, as non are true primaries like the above.