Concentrator

The Concentrator, also known as the Conc Barb, is the opposite of most other builds. Instead of focusing on dealing massive damage, the Concentrator focuses mainly on his defense.

Stats
Strength: Enough to equip desired gear.

Dexterity: If choosing a shield for this build, add enough dexterity to bring block to 75%, otherwise, enough to equip desired gear.

Vitality: The Barbarian has the best Health gain per point in Vitality. Any extra points to spare should go here.

Energy: Any respectable Concentrator should ignore Energy completely, as Concentrate has a very small cost of Mana.

Primary Skills
These skills should have a 20 point investment:
 * Concentrate: Main Attack.
 * Battle Orders: Synergy skill. Also convenient since this skill is popular for the life and mana boost.
 * Synergy skill.
 * Weapon Mastery: While defense is key with this build, the critical strike chance as well as the attack and damage bonus are also great perks.

Prerequisite and Secondary Skills

 * Berserk (1+): Synergy skill for Concentrate. On its own, it deals 100% magic damage, useful for physical immunes and being cursed with Iron Maiden (reduced to hostile Necromancers in PvP), its drawback being that the player's defense drops to zero for a short duration. Although 1% magic damage is considered quite small, fully investing in Berserk might add enough pure magic damage to avoid having to switch directly to this skill, but it would take up a lot of skill points a player might wish to invest elsewhere.
 * (1): Prerequisite for Battle Orders. Has use in breaking up mobs of monsters in melee.
 * Shout (1+): Increases party's defense, quite useful and doesn't suffer the diminishing returns found on many other skills. Prerequisite for Battle Orders.
 * Stun (1): Prerequisite for Concentrate

Optional Skills

 * Iron Skin (1+): Passively boosts defense. Also has linear progression.
 * (1+): Passively boosts resistances. It is not recommended to invest more than two points due to the steep diminishing returns after level 2.
 * Battle Command (1): Boosts skill levels. Most only ever put one point due to the fact the skill bonus is only one point regardless of investment.
 * Increased Stamina (1): Entirely optional, but usually taken as a prerequisite for the Increased Speed skill.
 * Increased Speed (1): Entirely optional, but having a natural boost to the character's walk/run speed has its perks
 * (1): Prerequisite for Battle Cry and/or War Cry. Causes monsters to melee with the characters, meaning that non-unique ranged monsters will walk up and attack at melee range.
 * (1): This skill not only penalizes an opponent's attack power, but also their defense rating, and virtually nothing can be immune to its effect. It can be overridden with a curse, but if a player is running solo or without the aid of a Necromancer, this can help a player hit monsters.

Equipment

 * Helm
 * Arreat's Face: +2 All Skills, Life Steal, Resistances, Bonus to Attack Rating.
 * Guillaume's Face: Crushing Blow and Deadly Strike.
 * Crown of Ages: +1 To All Skills, Damage Reduction, Resistances, Socketed.
 * Vampire Gaze: Dual leech, Damage Reduction.
 * Stealskull: Increased attack speed, Dual Leech.
 * Tal Rasha's Horadric Crest: Dual Leech, Resistances.
 * Crown of Thieves: Life Steal, Fire Resistance.


 * Armor
 * 300% Enhanced Damage, Faster Cast Rate, Resistances.
 * +2 all skills, resistances, damage bonuses.
 * Enhanced damage, Crushing Blow, Open Wounds, Resistances.


 * Belt
 * Nosferatu's Coil: Increased attack speed, life leech and slows target.
 * String of Ears: Physical damage reduction and life leech.
 * Arachnid Mesh: +1 to all skills, slows target and mana related skills.


 * Gloves
 * Steelrend: Enhanced damage and crushing blow.
 * Laying of Hands: +350% damage vs. Demons.
 * Dracul's Grasp: Open Wounds, Massive life leech.
 * Soul Drainer: Dual leech and Lowers Monster Defense.
 * The Hand of Broc: Dual leech. Also easy to find.


 * Boots
 * Gore Rider: Open Wounds, Crushing Blow and Deadly Strike.
 * War Traveler: Damage and stats bonuses. Magic find.


 * Amulet
 * Highlord's Wrath: +1 All Skills, Increased Attack Speed and Deadly Strike.


 * Rings
 * Bul-Kathos' Wedding Band: +1 to all skills and Life-related bonuses.
 * Raven Frost: Cannot be frozen, bonuses to dexterity and attack rating.


 * Weapon (Two-Handed)


 * Weapon (One-Handed)


 * Shield

Hireling
The Act II Desert Mercenaries with Might seem to help the Concentrator dispatch enemies much quicker. Even faster if they would be equipped with a Pride Rune Word.