Vanquishing all campaigns

Bring a friend (not a pug) who is not stupid. The benefits from this are many and mighty, from the indirect (someone to talk to while vanquishing) to the direct and mighty (heroes and henchies can't split up to search for that last @#$!$! patrol on the far side of the map then ping you to them).

Bring DP removal for the hard areas (a lot of areas you don't need it. Like all of Norn territory and the first half of Elona)

Have a good collection of MP3s (or an mp3 player if your PC can't play GW and decode MP3s at the same time) because you are going to be awhile.

Vanquishing can be fun (done Cantha and Elona so far, working on prophecies), just don't bring the same builds everywhere otherwise you will get really bored. If you Discordway/Sabway the entire thing you are going to want to kill yourself. If it starts to feel un-fun, stop and come back 3-4 months later when the skills have all been changed around and there's new gimmicks available. I've been doing it piecemeal over the last 2 years.

My wife vanquished all three campaigns pretty much just H/H, and one piece of advice she gave me was that doing a long pull (getting a mob to follow you and string out) is very very useful.

Yesterday, I vanquished Tasca's Demise doing this and managed to take out the large central mob of Stone Summit easily by using this tactic. I did suffer a few deaths, but it could have been so much worse. They had four Dolyak healguys!

I got legendary vanquisher about a week ago, the best advice possible is to have a friend along with as much as possible. I found working with a friend could sometimes knock 1/3 of my vanquish time off

My advice is to look at what creatures are in the area and to always be preprared for the worse, trust me if it can happen it will happen. Something small like one of your heroes dying can give the oposing mob to cause a decent number of deaths. No matter what enchant removal and aegis will become your best friend during your vanquishing run. I found the centaur healers pretty decent and got unlucky in Anvil Rock when I had a group of 4 centaur healers and one boss healer, too me a while to wall block on of them at a time, but I still won.