What do you guys think of this challenge?

[TemjinGold]

Yep, no-loss is not a requirement as that isn't possible for even the training fights. I guess the Princess Set and Skellie Archers would see a lot of use...

[KongMysen]

KB scanner for the +1 dmg items. + resistance things.
Funny how "no-loss" has been so custom in here that anyone incl. myself except zechnophobe just assumed this was a no-loss game.

I really love the idea, and I think I'm going for it once I complete Mass Effect 2.

Btw Kiting allowed?

[DGDobrev]

Should be. Otherwise you'll have to clean up debir with minimal firepower

[fable]

I guess you meant "map kiting". It probably doesn't make a difference anyway, because with these rules, the end of the game will be hard, and map kiting only helps the startup.

I'm actually doing a level 1-2 run with my paladin, and no map-kiting. It's lots of fun, so I really recommend giving it a try.

Dryads are amazing, I got to montero with them at level 10, and they help a lot with no-loss fights for the medal. I use 4 stacks of them, plus marauders for cash. The Verona-map guard army had 2 stacks of berserkers, they're immune to mind spells, so I held them back with lots of thorns. The rest were put to sleep by dryads. The endless bridge guard was 2 stacks of demons plus sleeping units. Similar fight but trickier. I could only damage them with marauder's lunge attack, because attacking with lower-initiate troops would cause them to take another turn.

I'll be facing some heavy losses mid-game. I got lots of +damage items, with assasin's dagger and crown of blackthorn the Thorn Hunters are doing 3-5 damage. I saved up all runes for Ressurect 3. And I have the marauders for money. I found an army of level 1-3 in the abandoned mines, and phantoming marauders yielded 70k cash. These are going to be tough times, still.

I also have a long term plan. Lots of physical resistance items, and miners. Twinkling boots (15), slippery cuirass (10), scale set (20), medal (7), stone skin (40) to a total of 92%, and for the miners, the Ice version of Axe of the Elements gives another 10% and "no retaliate". Swordsman and Cave Spiders also have 20% physical resistance.
Zigaldis will be problematic, I'll try to kill it fast with all magic resist gear.
K'tahu is all-physical damage but tirexes fear, and summoned gorgonuas deal magic damage. Still, this should be the easiest of the 3.
Baal, I'm a bit worried about the fire based area effect.

I wonder what can I do with dragons though. Emerald does physical, but no real protection from the others.

@Temjin, what's wrong with mythic egg? With my warrior, half the time I preferred ball lightning over it, and in most situations they were roughly the same. With less leadership as a paladin, it's even less powerful. I didn't rely on it yet, but I'm planning to use it, this extra choice richens the game experience without trivializing it. Well, probably it's different if your rest of the army is level 1-2.
I know you completed the game on the back of demon portal as a mage, so I agree with that restriction.

@DGDobrev: "Other difficult armies to beat will include dryads, evil eyes/beholders (their sleeping attacks seems to proc against lower level targets much more often), and others."
My current nightmare is werewolves, their mass-fear completely neutralizes my whole army. I'll level up a bit more and go back with undead units and fire spiders. I've killed some dryads though, I put them to sleep first

[TemjinGold]

I guess it was to put more emphasis on the army. My brother completed the game with a warrior by basically waiting for the egg to hatch.

[Zechnophobe]

Beholders always paralyze level 1 units by the way. I think I remember the odds being 1/(unit level) with level 5's excluded. Might be wrong there, but I do know you always paralyze level 1's, and often paralyze level 2's.