I know you need 18 or 19 wells for this achievement.
for my lvl 50 champion class has 18 wells(i've replayed the campaign mode over and over) but so far I haven't gotten it with him yet.
while my lvl 30 Berserker start off with 13 wells( now 14 just started the campaign mode again and now I'm in the ice forest)
my question: I quit(not going back to the Aesir) near the beginning of a level(like the ice forest) does this glitch the achievement? What about replaying the campaign mode over with new game+ character does that glitch up the achievement?
what about the extra wells in side of World Tree(where the NORDs live) do any of those count? --- "there's a book that claims the world was created in 7 days a best seller too"- Vidic
Xbox360achievements.org has an achievement guide and in it it gives some info on helping the cheevo pop.
I only skimmed it but it seems you will have to do another NG+ with your champ or finish your playthru with the zerker. Use the checklist linked on that page to determine which ones you need and where they are.