Ok I'll bite... 9 challenges is hard. I understand the discouragement but it we l sounds like you have the perseverance you need to get it done. That's a hard-earned quality.
To get this done you either need to outheal the damage you take (with no armor) or not get hit to begin with.
For outhealing, mage will work but not until you can subclass warlock. It's tough to get to that point unless you have amazing weapons like corrupting or vampiric. You need something that hits hard and accurately. You can't afford to take extra hits.
For not getting hit, I prefer rogue because you can lean into evasion much more easily by augmenting the cloth armor for evasion because it works well with the free runner subclass. You have to be careful with your scrolls but at least 1 upgrade into cloth armor on rogue can increase evasion (str requirement on free runner) and gives stone of augmentation a boost as well. Freerunner with ring of sharpshooting and/or crossbow is amazing and can win you the game but it's always down to luck at times. A missed hit, an unseen evil eye, the wrong champion in the wrong place, all of those can still end your run. Sometimes you just have to run away rather than fighting.
Personally I prefer to not get hit but I've made both work. It's more about knowing how to use what you get rather than getting the exact thing you want.
A few other things to look out for on your quest which can help: -anything that generates health or shielding (character abilities, wand of transition, wand of living earth) -anything that can increase your evasion (stone of augmentation on armor, ring of evasion) -anything that puts distance between you and enemies (ring of haste, wand of blast) -anything that negates damage (ring of elements, potion of arcane armor, potion of earthen armor) -shields (but they can only take you so far since they don't hit hard) don't over-invest -artifacts that let you escape bad scenarios (cloak, chains, hourglass) -potions/scrolls that let you escape bad scenarios -ring of wealth (this one sounds like it wouldn't help that much but when you can't heal, having extra scrolls/potions can really be a big boost -there's other strategies as well, but a glyph of stone can actually be incredibly powerful with the right combo of augmentation and supporting rings (evasion, arcana) you can tank any physical damage with this combo or if you find A ring of elements or glyph of magic, you can also tank magic damage