It was how to kill a mummy.
There are anti-bash preps that are not readily dispelled, and a mummy can get them. And layer them on top of wraithform.
There isn't, to my knowledge, a decent defense against the exotic lagging skills.
Plus choosing one legacy doesn't limit your character that much. You seem to be making out that a character that chooses this can't do much else.
If you want cookie cutter, I'd say outlander druid. You have a chance to catch/get mummy in lag and he's vulnerable to some of your nicer supps.