A strong method of preventing these kinds of party wiping headaches is a mage/rogue combo. Start with Scholar or Apprentice, and then with 40 wits get Caster. This unlocks the "lightning" and "blizzard" spells. Lightning has a 100% chance to stun most characters, and blizzard hits the entire enemy party and can freeze a number of them, giving you a bit of breathing room if you're feeling overwhelmed.
Then take classes like Rogue and Archer for some bonus speed (both +10), so your mage can act first and neutralize the heavy hitters.
Take care though! Some boss monsters have high resistances to being stunned, so don't get too comfortable stunning first and asking questions later. The Mimic is likely the first such monsters you'll come across, and I found this out the hard way...
edit: your characters gain stats by either using those types of attacks, or doing that kind of work. i.e. casting spells and fishing are both ways to increase your Wits over time.
Viewing post in Lich----Decay
Caster is helpful *IF/WHEN* you can get it (remember we're talking about facing the Lich b4 D28---very rare to have more than 1 Caster) + Lich's have hi water Dam resist, so does very little Dam. Ya mimic's R a PAIN (but if you're prepped 4 bosses they're not too bad---single target, no *MASS* damage)
There's some irony---all this talk about Magic Dam----& best way found so far is 1) AVOID! (w hi Physics you can talk him out of it *AND* rescue girl!) or 2) old fashioned *PHYSICAL* (Lich has low armor) Even 2 hi quality swords (no hi lvl classes needed!) help a LOT. SPEED helps too. Assume bad luck, so % chance (freeze?) means it usually won't work , *OR* misses most imp char (boss/Lich/etc)
Don't rem----is Lich immune to "stun?"