Finding a common tactic with the caster Fableds (Ishva, Undertow, Kobold Noble, etc) that works very well, so much so that you can do them without a healer.
EG Undertow tonight
Bard, Ranger, Monk, all only VT equipped. Monk uses all defensive discs while Ranger uses trueshot and bard sings his stuffs, Ranger then uses weaponshield while monk uses offensive discs, finally bard sings DA while we healed up a bit and finished him off.
Since all the caster mobs have the mana of a lvl 65 (which most of them are), but the hitpoints of a trash mob, you can beat them down very fast while they cast lvl 40ish spells on you. Once they start hitting you, even for 1.3k like Undertow, it's then pretty simple to disc and finish them off. Stuns also work well if you have a pally / chanter / wizzie.
Fun mobs to push yourselves on, since they haven't been done over and over with tactics perfected and known to the world.