Diablo III- Skills Article CXXXIV: The Wizard, Conjuration Skills- Ice Armor

Ice Armor (25 Arcane Power): For the next 120 seconds, you are protected by a barrier of ice that Chills or Freezes enemies that hit you in melee (random chance between the two).  You can only have one Armor spell active at a time.

Familiar to all those who used Shiver Armor in Diablo II, the Ice Armor spell does pretty much what you’d expect- slows or stops things after they hit you, reducing incoming damage and, if necessary, giving you a chance to get away.  Of the Armor skills, this is the one that is most useful to all kinds of Wizard; short-range, long-range, and variable-range wizards can all benefit from the effect this spell has on melee attackers.  It’s not necessarily the optimal choice, but whether it is depends on the Wizard in question.

Chilling Aura (25 Arcane Power): For the next 120 seconds, you are protected by a barrier of ice that Chills or Freezes enemies that hit you in melee (random chance between the two).  Additionally, enemies within 14 yards of you are Chilled and will continue to be so for 3 seconds after leaving this area of effect.  You can only have one Armor spell active at a time.

The basic rune for Ice Armor is, like the core skill, useful to Wizards of all types.  When you want to face enemies close up, it reduces their attack speed and their ability to get into a good position to attack you- or out of position for you to attack them.  When you want your enemies farther away, this gives you a chance to back off while they’re delayed.  Either way, Chilling Aura is a strong boon.

Crystallize (25 Arcane Power): For the next 120 seconds, you are protected by a barrier of ice that Chills or Freezes enemies that hit you in melee (random chance between the two).  Additionally, when you are struck with a melee attack, your Armor is increased by 15% for 30 seconds.  This effect can stack up to three times, for a maximum increase of 45%, but it will expire when Crystallize expires, even if its own duration hasn’t ended yet.  You can only have one Armor spell active at a time.

Crystallize is primarily for short-range Wizards.  The armor-boosting effect is far more useful in melee, where most enemies deal out physical attacks that are affected by armor, and most close-combat Wizards can keep the boosted armor rating up for as long as they feel like.  Stacked together with the Chilled/Frozen effect on enemies that hit in melee, you’re looking at a seriously effective form of damage mitigation here.

Jagged Ice (25 Arcane Power): For the next 120 seconds, you are protected by a barrier of ice that Chills or Freezes enemies that hit you in melee (random chance between the two) and deals 100% weapon damage as Cold damage to them.  You can only have one Armor spell active at a time.

Jagged Ice is a bit odd- if you’re going to be in close range as a Wizard, you need the survivability of something like Crystallize more than you need the retributive damage.  Where Jagged Ice comes in handy is if you’re fighting at range against large monsters, and smaller, quicker melee creatures like Fallen or Imps keep darting around your main skill effects and closing in with you.  The fact that each creature gets at least one attack in anyways means that this isn’t a good defense against large masses of enemies, and since retributive damage doesn’t work well with effects that slow incoming strikes (like Chilling and Freezing), you’re better off not bothering with this rune most of the time.  If you’ve set up your gem slotting to massively boost your endurance, this may be an okay rune, though.

Ice Reflect (25 Arcane Power): For the next 120 seconds, you are protected by a barrier of ice that Chills or Freezes enemies that hit you in melee (random chance between the two) and has a 25% chance on each hit to generate a Frost Nova as per the skill and deal 75% weapon damage as Cold damage to all enemies struck by that Frost Nova.  You can only have one Armor spell active at a time.

Ice Reflect is a rune that again is for all forms of Wizard.  Since the Frost Nova it creates is exactly like the basic Frost Nova for the skill (with an addition of some damage), it freezes enemies solid in a rather large radius.  This gives plenty of opportunity to either escape or hand out extra damage whenever it triggers, making it effective no matter what you want to do- as long as it triggers.  Ranged-attack Wizards will rarely want to be close enough to enemies to take enough hits that the effect will trigger, so for them this is more of an automated panic button, but close-range Wizards should find this effect going off regularly.

Frozen Storm (25 Arcane Power): For the next 3 seconds, an ice storm builds in the area around you (roughly a 14-yard radius), dealing 10% weapon damage as Cold damage per second to all enemies in its area of effect.  For the next 120 seconds, you are protected by a barrier of ice that Chills or Freezes enemies that hit you in melee (random chance between the two).  You can only have one Armor spell active at a time.

Pretty much the opposite of Ice Reflect, Frozen Storm acts as an emergency button you can trigger when you’re getting overcrowded.  The effect isn’t worth the Arcane Power cost of the entire spell, so this is more likely to be useful for a long-range Wizard who can take advantage of the chilling effect that cold damage automatically has to get out of a dangerous situation.  Close-range Wizards have better rune options for Ice Armor than that.