Monster AI Prioritize Armor More or Health More?

Does anyone know if the target choice of monster AI depend more on AL or health? If one Hero 1 has 10 more AL but 30 less health than Hero 2, which hero will be targeted first by monster AI? (assuming both heros are the same distance away from the monster and all other aggro conditions are the same regarding both heros) Thanks in advance.

I think they target lowest health first.

i'd have to assume armour, thinking that when me and my friend are together, both rangers same armour insignias and runes, he wields a sword of defence and a shield while i wield a +60 staff, giving me more health and him more armour, they go for me.

Enemies also prioritize by class. For example, they will usually go after monks even if a nearby ritualist has less armor/health. I don't think enough research has been done or can be done to narrow down the exact equivilence rate. Distance is also a factor.

Health is a very big determining factor, as running Vital Blessing on my Elementalist, even midline, (700hp) I almost never get targeted, maybe hit with 1 or 2 attacks every couple mobs.

Using an E/mo ether renewal healing build I would guess?

Otherwise the enemies are probably ignoring you because having vital blessing is a pretty useless thing on an ele.

Yea Ether Prot, spamming Shield Guardian and RoF, all while under the effects of Vital, Ether Renewal, Mind Bender, and Zealot's Fire is godly support

They don't recognize class and I can prove it. You know those storm kin or whatever those floating mesmer things are outside of Serenity temple. While wielding a sword/axe/spear(I used axe) and a shield they won't cast backfire on you even if you are a caster. Thats how I vanquished that area with 4 casters. We all switched to axes and shields when we fought those.

Its attacking not casting hexes on... No AI will put backfire on a physical (or so they think), but they will attack the monk over the ele, etc.

This I feel is a complicated question.

Normally if it's a caster shutdown monster, they'll target a person if they have a caster weapon (i.e wand or staff)-switching away from those prevents most of the nasty stuff like Backfire.

They'll generally look and see what the person is using-if someone is using healing skills, they'll target them first. Same with saccing skills.

If for some reason they can't get to either of those, they'll go for the lowest armor character.

For an example, on my paragon I use [save yourselves] with a N/Rt restorer with [dark fury] and [order of pain]. My N/Rt is now a prime target-not only is she healing, but she's also saccing health-so the AI will generally want a piece of her first. However, if they can't reach her or kill her (which is hard since I'm pumping out +100 armor), they'll switch to me-the lowest armor party member.

No one knows for sure. Not enough research has been done.

If I had to take a guess, they are probably looking at something that approximates BADITTKY - Before-Armor Damage It Takes To Kill You. That is, the monster bases its decision on the amount of raw damage it would take to kill each party member, taking into account their current life and armor. Let me repeat: that's just my best guess; I do not know for sure.