I’ve tried 3 outdated builds: vitality cooldown caster conjurer, elemental pew pew and spin2win shiledbreaker, and I feel they’re all capable to finish the campaign at least. I have a total cruise over the campaign with the spin2win especially, because it’s really easy to gear:
[1.1.4.2-1.1.8.1] Shieldbreaker from A to Z, including end game, budget build+leveling guide
I haven’t yet finished ultimate with it however.
edit: more precisely. I’ve indeed finished the campaign with my Dark One’s Vitality Conjurer (see guide from Nery). It’s a very tough build, but not a very fast killer ; I kill random stuff much faster with my fire spin2win shieldbreaker. The conjurer can face tank and kill some serious stuff though, like Mogdronen or Ravager. I’ve not tried that yet with the shieldbreaker.