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Your defenses are your ability to protect yourself against various types of attacks, such as goblin swinging a sword at you or a wizard casting fireball. Different defenses will protect you from different attacks. Each of your defense scores follow the following formula:

10 + (half your level) + (armor or shield bonuses if applicable) + (ability modifiers) + (feat, race, untyped, etc bonuses)

There are 4 defenses:

  • Armor Class (AC): Your armor's effectiveness and your ability to dodge or deflect physical blows is measured by your AC. The armor you wear, the type of shield you use (if any), and possibly your Intelligence or Dexterity all contribute to this.
    • If you wear light armor (cloth, leather or hide), add either your Intelligence modifier or Dexterity modifier to your AC (whichever is higher).
    • You do not take a penalty if one modifier is negative but the other isn't. For example, if you have 12 intelligence and 8 dexterity, you gain +1 to your AC from intelligence instead of 0 or -1. If you roll your stats and your intelligence is 8 and your dexterity is 3, then you would only take a -1 to AC because intelligence has the highest modifier.
  • Fortitude is your ability to endure physical stress, poison, intense pain, etc. Your Strength or Constitution modifier (whichever is higher) increases this defense.
  • Reflex measures how well you react to incoming dangers, either dodging out of the way or shielding yourself from the brunt of the attack. Many spells and some physical attacks target your reflex defense. Add the higher of your Dexterity or Intelligence modifiers to this defense (again, you don't take a penalty for a negative modifier if the other modifier is positive). In addition, equipping a shield will add to your Reflex defense.
  • Will is your willpower in fighting against effects that try to affect your body or mind. Many physically and mentally harmful powers target your will, including mind control and domination effects. Add your Wisdom or Charisma modifier to this defense, whichever is higher.

When an attacker makes an attack roll, it must equal or beat the targeted defense to qualify as a hit. Some powers take effect on a miss too, though with limited potency.


Feat Requirement Benefit
Agile Command Warlord, Int 15, Skirmishing Presence class feature, level 11+ Any ally that starts their turn adjacent to you gains a feat bonus to AC and Reflex against opportunity attacks
Armored Warrenguard Gnome You do not suffer the normal speed penalty incurred by chainmail and scale, and gain +1 bonus to AC from Large or larger enemies.
Brawler Guard Fighter, Brawler Style +1 Shield bonus to AC and Reflex when one hand is free
Dodge Giants Dwarf +1 to AC and Reflex against attacks of Large or larger foes
Elusive Movement Ranger or Rogue, level 11+ +1 AC and Reflex if you moved at least 3 squares
Evasive Footwork Rogue, Dex 17, Cha 15 +1 to AC and Reflex when you shift 2 or more squares
Frozen Soul Constitution 13 or Wisdom 13 +1/+2/+3 Will Defense, Resist 5/10/15 cold
Great Fortitude - +2/+3/+4 Fortitude
Hafted Defense - +1 AC and Reflex while wielding polearm or staff in two hands
Human Soul Human, Revenant +1 to Fortitude, Reflex, Will
Improved Defenses - +1/+2/+3 to Fortitude, Reflex and Will
Improved Staff of Defense Wizard, Staff of Defense class feature, Con 13, Dex 13, level 11+ While wielding a staff, gain +1 Fortitude, Reflex, and Will
Iron Will - +2/+3/+4 feat bonus per tier Will defense
Last Legion Officer - Ally can shift 1 sq. or gain +2 to AC and Reflex until the start of their next turn when you target them with a power that lets them spend a Healing surge
Lightning Reflexes -, (was level 11+ initially, see feat page) +2/+3/+4 feat bonus per tier to Reflex
Nimble Runner - +2 Reflex when running, don't grant combat advantage when running
Rod Expertise - +1 to attack rolls, AC and Reflex when holding a Rod
Shield Defense Wis 13, Fighter +1 AC and Reflex when a power requiring a shield hits
Shield of Darkness Drow +2 to Reflex while within your Cloud of darkness
Shield Specialization Shield Proficiency (Heavy or Light), Dex 15, level 11+ +1 to AC and Reflex when using a shield
Small Warrior's Defense Fighter, Small size +2 to AC and Reflex when you hold a versatile weapon with both hands
Snowdown Courier Moonshae Isles regional benefit +2 to AC and Reflex against Opportunity Attacks when you run; +2 to Streetwise
Superior Fortitude Strength 15 or Constitution 15 +2/+3/+4 Fortitude defense, Resist 3/6/9 to ongoing damage
Superior Reflexes Dexterity 15 or Intelligence 15 +2/+3/+4 Reflex defense, gain combat advantage against all enemies during first turn of encounter.
Superior Will Wisdom 15 or Charisma 15 +2/+3/+4 Will defense, make saves against Dazed or stunned condition
Two-Weapon Defense Dex 13, Two-Weapon Fighting +1 to AC and Reflex while holding a weapon in each hand