[Saber Cherry]

Things that reduce afflictions:

Regeneration - any amount, no matter how high or low - cuts affliction rates to 1/8. Undeads other than Vampires cannot regenerate, so they are more vulnerable. That's one reason I like Ice Devils as SCs.

Luck reduces successful hits by 1/2, which reduces affliction rates by roughly 1/2 (possibly more, due to various cumulative side-effects).

Ethereality reduces non-magical hit rates to 1/4 or less (I think that ethereal targets do not suffer the defense penalty from attacks that miss due to ethereality), and thus cuts affliction rates to roughly 1/4 versus a purely mundane army, or not at all versus mages, enemy SCs, and anti-SC squads.

Mistform reduces damage to 1, which makes afflictions highly unlikely. Of course this is not a really good solution for most SCs because it requires air magic, along with Mirror Image.

Air Shield reduces normal projectile hits to 20%, cutting afflictions from that source. Crossbows are dangerous to SCs.

Defense, protection, and resistances obviously reduce afflictions by reducing damage from relevant sources. Protection is usually better since it is not reduced after every strike, works against projectiles and AOE attacks, and reduces damage even if the opponent rolls higher than the defender. Consult the dice-roll-chart thread for exact numbers in a given situation. Hydra Skin Armor and Black Steel Full Plate cannot be compared without knowing the stats of the attacker(s) and defender.

Reinvigoration and/or lifedrain prevent fatigue buildup. Fatigue reduces defence and protection, which increases damage and thus afflictions.

High hitpoints reduce afflictions because the probability of receiving an affliction from an attack that does X damage is X/(MAX HP). Please note! This makes pretenders and prophets HIGHLY vulnerable in hostile dominion, where a dragon might have a temporary "256 current HP," but due to hostile dominion, only "32 max HP." Inflicting a non-fatal 128 damage on this dragon (by multiple attacks, like crossbow bolts) will cause an average of 4 afflictions!

Immortality makes afflictions almost irrelevant, since immortals heal their own afflictions very rapidly. Thus, even though undeads cannot be given regeneration, many of the best ones don't need it anyway...


Things that increase afflictions:

Curse gives a base 25% chance for any damaging attack to cause an affliction. So once a combat unit is cursed, it's done. Luck does not counter curse. However, I think regeneration reduces affliction rates from Curse to 1/8 of normal, or about 3%.

Things like Blindness, Heart Finder, Eye Shield, and various artifacts cause afflictions that cannot be prevented by anything.

Seeking Arrow causes an affliction if it hits and does damage, but Luck, Air Shield, extremely high protection, and (possibly) good shield will prevent this.

Disease causes afflictions, but they seem to be reduced by regeneration, from my observation.


So, as to your questions:

Regeneration is vital.
A Pendant of Luck is worse than a Ring of Regeneration.
Hydra Skin Armor versus good armor: It depends.
Never send a cursed pretender alone versus massess of weaklings... unless he is healing or immortal, or regenerating and lucky and high protection and (ideally) a trampler. Units with trample like Earth Mothers don't suffer much from afflictions.


Edit: Note that all this is from my memory and I have a very bad one. But I'm very certain about most of it.