Like I said in the description, this is simply a written version of A Kis Herceg's video on the topic. You can check the original video below:

https://www.youtube.com/watch?v=M_j4lhBU0CI
Basically, since the AI is bad at making decision you need to simplify their choices. That means limiting which skills they can use and focusing on the ones they can use effectively as well as supporting combos, even more so interclass combos that play to the player's character.

At any given moment the AI has to decide what to do and it follows the formula

If X happens, then do Y

So for example

If enemy has a barrier, then use Dispel

Except the AI is garbage at this

It usually fail to recognize all the factors it needs to take into account and if it has too many options of what to do it'll probably not pick the best choice. There's nothing we can do about the first part, but about the latter we can tailor the Tactics setting for each companion to maximize their effectiveness.

Each skill in the Tactics menu has 3 settings:

DISABLED: the AI will never use this skill
ENABLE: the AI can use this skill
PREFERRED: the AI will prioritze this skill whenever possible

Basically, to create a proper AI build you need to know which skills to focus on, which ones that are good to have but are not the base of the build and which ones to avoid. That's exactly what this guide is for.

DOUBLE DAGGERS

• FLANK ATTACK (SKIRMISHER) - provides bonus damage and some protection, the upgrade puts them in stealth, which adds survivability and damage
  
• DEATHBLOW (THRILL OF VICTORY) - good for an aggressive rogue, great combo detonator

ARCHERY

• LONG SHOT (EAGLE EYE) - set this to 'preferred' so your archers keep their distance in battle, the upgrade increases damage without you having to worry about friendly fire
  
• FULL DRAW - for an archer that keeps distance from the fight, this can deal massive damage, both upgrades are good depending on what you want
  
• LEAPING SHOT (SHOT FROM THE SHADOWS) - the skill itself is not great for the AI, but the upgrade puts them in stealth until their next attack, adding to damage and survivability
  
• EXPLOSIVE SHOT (CHAIN REACTION) - great skill for the beginning, especially combined with Poisoned Weapons since fire/poison bypass armor, but don't use this with friendly fire on
  
• PINCUSHION - this passive is recommended for all rogues since it increases damage with each attack (despite saying it applies only to bows, it actually works with daggers as well)

SABOTAGE

• POISONED WEAPONS - buffs in general work great with AI, poison bypasses armor and the upgrades add lifesteal for survivability (Leeching Poison) or damage (Infected Wounds)
  
• THROWING BLADES (PRECISION TARGETING) - a must for rogue allies
  
• TOXIC CLOUD (LOST IN THE MIST) - useful if surrounded by enemies, better for melee rogues
  
• LOOKED LIKE IT HURT - great passive for builds that focus on critical chance, giving more stamina

SUBTEFURGE

• STEALTH (CLINGING SHADOWS) - strongly recommended for survivability and damage, the upgrade keep both benefits for longer
  
• SHADOW STRIKE (LONG SHADOWS) - great for stealth characters, the upgrade allows use on ranged enemies

ASSASSIN (COLE)

• HIDDEN BLADES - works fine, the upgrades depend if you want more single target damage (Overkill) or 'AoE' (No Wirnesses)
  
• MARK OF DEATH (LASTING MARK) - for additional damage, the upgrade is a must for AI

ARTIFICER (VARRIC)

Artificers are great for the party mainly because of their passives

• SPIKE TRAP (PYROTECHNICS) - a protective skill that blows up anyone who gets too close

TEMPEST (SERA)

• FLASK OF FROST (FROSTBITE) - useful if the AI is surrounded and needs protection, it's more useful on a dual dagger Tempest
  
• FLASK OF FIRE (UNQUENCHABLE FLAMES) - can work with fast hitting skills like Throwing Bladdes or Deathblow, the upgrade removes the cooldown of skills for the duration
  
• LIGHTNING FLASK (THUNDERSTRUCK) - when used by an AI grants it extreme speed increase, best skill for an archer Tempest AI

Regardless of what type of weapon Cole uses, STEALTH is the foundation of his build since his specialization Assassin is built upon STEALTH.

DUAL DAGGER ASSASSIN

• STEALTH (CLINGING SHADOWS) - Preferred
  
• POISONED WEAPONS (LEECHING POISON) - Preferred
  
• MARK OF DEATH (LASTING MARK) - Preferred
  
• FLANK ATTACK (SKIRMISHER) - Preferred
  
• DEATHBLOW (THRILL OF VICTORY) - Preferred
  
• HIDDEN BLADES (OVERKILL) - Enabled

ARCHER ASSASSIN

For an Archer Cole, ranged skills must be set to 'Preferred' so he'll keep his distance.

• STEALTH (CLINGING SHADOWS) - Preferred
  
• POISONED WEAPONS (LEECHING POISON) - Enabled
  
• LONG SHOT (EAGLE EYE) - Preferred
  
• HIDDEN BLADES - Preferred (use NO WITNESS for multiple targets or OVERKILL for single target damage)
  
• MARK OF DEATH (LASTING MARK) - Preferred
  
• SHADOW STRIKE (LONG SHADOWS) - Enabled
  
• THROWING BLADES (PRECISION TARGETING) - Enabled

DEFENSIVE DUAL WIELD TEMPEST

This build focuses on rapid basic attacks, keeping Sera safe with Flank Attack. Sera is a great DPS that works best when attacking single targets.

• POISONED WEAPONS (LEECHING POISON) - Preferred
  
• STEALTH (CLINGING SHADOWS) - Preferred
  
• FLANK ATTACK (SKIRMISHER) - Preferred
  
• LIGHTNING FLASK (THUNDERSTRUCK) - Enabled
  
• PINCUSHION (passive)
  
• LOOKED LIKE IT HURT (passive)

Since she's a frontline fighter, you can enable FLASK OF FROST (FROSTIBE) for when she gets surrounded and DEATHBLOW (THRILL OF VICTORY) for low health targets.

For masterworks, I recommend Walking Fortress and Guard on Hit. Since Sera attacks super fast after activating LIGHTNING FLASK, she can make the most use of 'on hit' masterworks, especially AoE ones. Of course, be careful if playing with friendly fire on.

OFFENSIVE TEMPEST ARCHER

LIGHTNING FLASK turns Sera into a Machine Gun, so all you need is to make her basic attacks as strong as possible. While LIGHTING FLASK is on cooldown, supllement her damage by spamming THROWING BLADES after activating FLASK OF FIRE. POISONED WEAPONS (LEECHING POISON) grants impressive leech that keeps her alive.

• FLASK OF LIGHTNING (THUNDERSTRUCK) - Enabled
  
• POISONED WEAPONS (LEECHING POISON) - Enabled
  
• FLASK OF FIRE (UNQUENCHABLE FLAMES) - Preferred
  
• THROWING BLADES (PRECISION TARGETING) - Preferred
  
• PINCUSHION (passive)
  
• LOOKED LIKE IT HURT (passive)

Her gear should focus on Dexterity, Critical Chance and Critical Damage.

Varric is useful in any team because his buffs are so great. Since he benefits from critical hits from the whole party, he can use his skills very often. Here are the passive skills you must get:

• AND TAKE THEM DOWN - gives the whole party increased critical chance
  
• OPPORTUNTY KNOCKS - reduces Varric's cooldowns every time an ally crits
  
• TRICKS OF THE TRADE - increases damage and duration of the whole party's status effects

RANGED ARTIFICER

• LEAPING SHOT (SHOT FROM THE SHADOWS) - Enabled
  
• SPIKE TRAP (PYROTECHNICS) - Preferred
  
• LONG SHOT (EAGLE EYE) - Preferred
  
• FULL DRAW (STUNNING SHOT) - Preferred
  
• POISONED WEAPONS (LEECHING POISON) - Preferred
  
• EXPLOSIVE SHOT (CHAIN REACTION) - Preferred (don't use with friendly fire on)
  
• STEALTH (CLINGING SHADOWS) - Enabled

DUAL DAGGER ARTIFICER

Varric can be very effective with dual daggers thanks to his great cooldown reduction that lets him spam his skills and break aggro by going in and out of stealth.

• STEALTH (CLINGING SHADOWS) - Enabled
  
• FLANK ATTACK (SKIRMISHER) - Preferred
  
• POISONED WEAPONS (LEECHING POISON) - Preferred
  
• SHADOW STRIKE (QUICK BLADE) - Enabled (optional)
  
• DEATHBLOW (THRILL OF VICTORY) - Preferred
  
• SPIKE TRAP (PYROTECHNICS) - Preferred
  
• TOXIC CLOUD (LOST IN THE MIST) - Enabled (optional)

WEAPON AND SHIELD

• SHIELD WALL (CHEVALIER'S STEP) - the AI handles this skill very well, it's essential for a tank, the upgrade lets the character move faster and provides protection for nearby allies
  
• SHIELD BASH (RING THE BELL) - has some problems with targeting, but it's good for dealing with guard and detonating combos, the upgrade increases damage to guard
  
• PAYBACK STRIKE - great for the AI since it breaks stuns and provides a small AoE knockdown, the upgrades taunt enemies to keep aggro for your tank (Cruel Revenge) or increases damage (Sweet Revenge)

TWO-HANDED WEAPON

• MIGHTY BLOW - great without friendly fire as it provides AoE knockdown, both upgrades are fine depending on whether you prefer damage (Easy Target) or crowd control (Stay Down)
  
• POMMEL STRIKE - has some problems with targeting, but does high damage and stuns, both upgrades are fine depending on whether you prefer damage (Lightning Jab) or crowd control (Staggering Strike)

BATTLEMASTER

• GRAPPLING CHAIN - useful early game against annoying ranged enemies, the upgrade stuns the target (Give Them the Boot) or drags multiple enemies (Chains for Days), which is useful for AoE skills
  
• HORN OF VALOR (FORTIFYING BLAST) - the AI is good with buffs, the upgrade provides guard for the whole party, it's a must imo

VANGUARD

• WAR CRY (BATTLE ROAR) - must have for AI tanks, I go for this upgrade because it helps the tank keep aggro
  
• CHALLENGE (CALL THEM OUT) - great early on to draw aggro, upgrade removes the cooldown, I wouldn't have both this and War Cry on the same character, this is more for a secondary tank for when an enemy is targeting one of your allies
  
• CHARGING BULL (GORE AND TRAMPLE) - don't use with friendly fire on, the upgrade gives a free skill use
  
• LIVID (STILL STANDING) - great skill, it provides damage reduction and guard (from the upgrade) for surrounded tanks
  
• BODYGUARD (NOT TODAY) - set this as Preferred if your squad is squishy, the upgrade negates some of the damage entirely

CHAMPION (BLACKWALL)

• WALKING FORTRESS - invincibility is always useful, the upgrades can give you guard (Siege-Breaker) or focus (Focused Defense), which can be useful if you plan to use the ultimate Counterstrike often

REAVER (IRON BULL)

• DEVOUR (LIFEBLOOD) - the only skill you can rely on the AI to use, acts as a healing potion

TEMPLAR (CASSANDRA)

• SPELL PURGE (ANNULMENT) - AI can use it more or less effectively and even perform combos, the upgrade makes it useful against demons and it can be used to insta-kill spawning rift demons (just remember it's centered on Cassandra, so move her accordingly)
  
• BLESSED BLADES (IN THEIR BLOOD) - AI uses buffs well, provides extra damage for the whole party, the upgrade gives it more flexibility
  
• WRATH OF HEAVEN (EMBRACE THE LIGHT) - great skill for the AI without friendly fire on, it's an AoE stun that damage demons

Blackwall is easily the best tank in the game

WEAPON & SHIELD CHAMPION

This build focuses on defense and party protection. Since Blackwall is hard to kill he might as well soak some damage directed at his teammates

• SHIELD WALL (CHEVALIER'S STEP) - Preferred
  
• WALKING FORTRESS (SIEGE-BREAKER) - Preferred
  
• HORN OF VALOR (FORTIFYING BLAST - Enabled
  
• WAR CRY (CALL TO ARMS) - Preferred
  
• BODYGUARD (NOT TODAY) - Preferred
  
• LIVID (STILL STANDING) - Enabled (you don't want him to use this at the start of the fight, but when he's surrounded)
  
• PAYBACK STRIKE (CRUEL REVENGE) - Enabled

You can add CHARGING BULL (GORE AND TRAMPLE) if friendly fire is off.

For masterworks, any defensive ones will increase his survivability. Other good choices are masterworks that reduce costs or increase stamina.

Pick the passives from the Weapon & Shield and Two-Handed trees, they work regardless of what weapon you're using. My suggestions:

• Warrior's Resolve - restores stamina as you take damage, which as a tank you will
  
• Turn the Bolt - reduces damage from ranged attacks from the front
  
• Turn the Blade - reduces all damage from the front
  
• Bear Mauls the Wolves - no flank damage bonus for enemies and you're less likely to be staggered
  
• Flow of Battle - critical hits reduce cooldown
  
• Guard Smasher - bonus damage against guard

TWO-HANDED CHAMPION

The Two-Handed approach focuses on buffing the party and giving Blackwall some crowd control instead of letting him soak damage. Apart from the active skill selection, everything else I wrote above is also valid for this build (gear/passives/etc).

• WALKING FORTRESS (SIEGE-BREAKER) - Preferred
  
• HORN OF VALOR (FORTIFYING BLAST) - Preferred
  
• LIVID (STILL STANDING) - Enabled
  
• WAR CRY (CALL TO ARMS) - Preferred
  
• POMMEL STRIKE (LIGHTNING JAB) - Enabled
  
• MIGHTY BLOW - Enabled (with friendly fire off)

Cassandra is an effective tank and serves well as an ally to both keep aggro and buff the party. She also has great passives that benefit the whole team.

WEAPON & SHIELD TEMPLAR

• SHIELD WALL (CHEVALIER'S STEP) - Preferred
  
• PAYBACK STRIKE (CRUEL REVENGE) - Preferred
  
• WAR CRY (BATTLE ROAR) - Preferred
  
• LIVID (STILL STANDING) - Enabled
  
• CHALLENGE (CALL THEM OUT) - Preferred
  
• SPELL PURGE (ANNULMENT) - Enabled
  
• WRATH OF HEAVEN (EMBRACE THE LIGHT) - Enabled (with friendly fire off)
  
• BLESSED BLADES (IN THEIR BLOOD) - Enabled

TWO-HANDED TEMPLAR

With good equipment this build can AoE damage, killing crowds faster than any warrior, but Cassandra needs help staying alive.

• CHARGING BULL (GORE AND TRAMPLE) - Preferred
  
• LIVID (STILL STANDING) - Enabled
  
• POMMEL STRIKE (STAGGERING STRIKE) - Preferred
  
• SPELL PURGE (ANNULMENT) - Preferred
  
• WRATH OF HEAVEN (EMBRACE THE LIGHT) - Preferred
  
• MIGHTY BLOW (STAY DOWN) - Enabled
  
• WAR CRY (CALL TO ARMS) - Enabled

Take care with using this build with friendly fire on. It works best in a party that focuses on ranged and magical attacks. As long as she has support, Cassandra will get the job done.

Because the AI is terrible at using the Reaver's main ability Dragon-Rage, it's difficult to make Iron Bull an effective party member. Doing so requires massive investments in defensive and support skills without neglecting offensive ones. Even so, he's not a great tank, working better as a secondary DPS. His build is based on high speed, high base damage, critical attacks and damage buffs.

TWO-HANDED REAVER

• GRAPPLING CHAIN (GIVE THEM THE BOOT) - Enabled
  
• MIGHTY BLOW (EASY TARGET) - Enabled (if friendly fire is off)
  
• POMMEL STRIKE (LIGHTNING JAB) - Preferred
  
• CHARGING BULL (GORE AND TRAMPLE) - Preferred (if friendly fire is off)
  
• LIVID (STILL STANDING) - Enabled
  
• DEVOUR (LIFEBLOOD) - Enabled
  
• HORN OF VALOR (THAT'S THE SPIRIT) - Preferred

WEAPON & SHIELD REAVER

• GRAPPLING CHAIN (GIVE THEM THE BOOT) - Enabled
  
• PAYBACK STRIKE (SWEET REVENGE) - Preferred
  
• SHIELD BASH (RING THE BELL) - Enabled
  
• SHIELD WALL (CHEVALIER'S STEP) - Enabled
  
• CHARGING BULL (GORE AND TRAMPLE) - Preferred (if friendly fire is off)
  
• LIVID (STILL STANDING) - Enabled
  
• DEVOUR (LIFEBLOOD) - Enabled
  
• HORN OF VALOR (THAT'S THE SPIRIT) - Preferred

SPIRIT

• BARRIER - basic skill I'd put on all mages, Elegant Defense is better early on, but switch Energetic Defense once you have gear with cooldown reduction (Vivienne probably makes the most of this skill because of her Specialization's passives)
  
• REVIVAL - basic support skill, the upgrade provides necessary protection (in my experience the mages are the first to go down, which defeats the purpose of the skill, and when they don't die, they don't use this very well... I'd skip this if you're not playing above the normal difficulty)
  
• DISPEL - a must for all mages, the upgrade empowers both skills and barriers (Transmute Magic) or lowers the target's magical attacks (Strengthened Veil), you can use this skill to insta-kill spawning rift demons

STORM

• STATIC CAGE (LIGHTNING CAGE) - great for a crowd control mage, provides extra damage against bosses
  
• LIGHTNING BOLT - gives enemies a debuff that makes them vulnerable to other types of damage, great if your main character uses elemental attacks, both upgrades are great: for more damage (Exploding Bolt) or for more crowd control (Lightning Cascade)
  
• ENERGY BARRAGE (ENERGY BOMBARDMENT) - great for lowering resistances and applying status effects

It's a good idea to equip a character of this school with a Cold or Fire staff to take advantage of the lowered resistances

INFERNO

• FLASHFIRE (BLISTERING PAIN) - great for fearing and burning enemies, the upgrade increases fear duration, this is a must for Nightmare with friendly fire
  
• FIRE MINE (FLAMING ARRAY) - the AI uses this well, avoid like the plague if playing with friendly fire

WINTER

• WINTER'S GRASP - a must for offensive mages, great single target damage, provides detonation combos for warriors, if playing with friendly fire on use Winter's Ruin, otherwise use Winter's Chill for AoE effects
  
• ICE MINE (CHILLING ARRAY) - great for crowd control, avoid if friendly fire is on

KNIGHT-ENCHANTER (VIVIENNE)

• SPIRIT BLADE (AMPLIFIED BLADE) - can work with AI, but needs great gear
  
• FADE CLOAK (DECLOAKING BLAST) - invulnerability is always welcome, with the upgrade it boths replenishes barrier and does damage

NECROMANCER (DORIAN)

• HORROR (TERROR) - great for fearing and paralyzing enemies, a must for Necromancer AIs
  
• WALKING BOMB - avoid if playing with friendly fire, otherwise it's great for AoE (Virulent) or single target damage (Concentrated Detonation)

RIFT MAGE (SOLAS)

• VEILSTRIKE (PUNCHING DOWN) - great in the hands of the AI, provides damage control and with the upgrade basically unlimited mana
  
• STONEFIST - good for crowd control and defense, for AoE use Shatterstone or for guard damage/friendly fire on use Unblockable Force)
  
• PULL OF THE ABYSS - one of the best crowd controls, combine with Veilstrike to dominate, the upgrades can add damage (Devouring Veil) or weaken enemies (Shaken Veil)

CROWD CONTROL NECROMANCER

Although not as good at crowd control as Solas, Dorian can synergize Necromancer and Storm skills very well.

• HORROR (DESPAIR)* - Preferred
  
• STATIC CAGE (LIGHTNING CAGE)* - Preferred
  
• CHAING LIGHTNING (ARCING SURGE) - Preferred
  
• LIGHTNING BOLT (EXPLODING BOLT) - Preferred
  
• ENERGY BARRAGE (ENERGY BOMBARDMENT) - Enabled

*Combining the panic effect of HORROR with STATIC CAGE works great because enemies will try to leave the area and will then be pulled back while taking damage. In the video he recommends the TERROR upgrade for HORROR, but it immobilizes enemies which to me works against the whole idea. DESPAIR lets them run away to make the combo work while making them more vulnerable to damage. That said, I haven't tried the build so it's up to you.

As an additional suggestion, Storm skills lower the resistances to other elements, so it might be a good idea to give Dorian cold/fire staffs to use to take advantaged of this.

CROWD CONTROL RIFT MAGE

Solas is great at crowd control because he can make everyone frozen or throw them around.

• VEILSTRIKE (PUNCHING DOWN) - Preferred
  
• PULL OF THE ABYSS (DEVOURING VEIL) - Preferred (with friendly fire off)
  
• STONEFIST (SHATTERSTONE) - Enabled (if friendly fire is on, use UNBLOCKABLE FORCE)
  
• ICE MINE (CHILLING ARRAY) - Enabled (with friendly fire off)
  
• WINTER'S GRASP (WINTER'S CHILL) - Preferred (if friendly fire is on, use WINTER'S RUIN)

As you can see, this isn't a build I recommend using with friendly fire on.

Vivienne can be a tank mage that also provides crowd control or support for the whole party. She's the only mage fit to be in the thick of the battle. With SPIRIT BLADE favorited she can give your warrior barriers or inflict heavy damage with her skills. The only downside is that this build requires very good gear. Blade of Tidarion[dragonage.fandom.com] is recommended to keep her in melee range (it's possible to get a schematic for this weapon which can be used accross saves).

CROWD CONTROL TANK

• SPIRIT BLADE (AMPLIFIED BLADE) - Preferred
  
• FIRE MINE (FLAMING ARRAY) - Preferred (with friendly fire off)
  
• ICE MINE (CHILLING ARRAY) - Preferred (with friendly fire off)
  
• FADE CLOAK (DECLOAKING BLAST) - Preferred
  
• WINTER'S GRASP (WINTER'S RUIN) - Preferred
  
• ENERGY BARRAGE (ENERGY BOMBARDMENT) - Preferred

SUPPORT TANK

• SPIRIT BLADE (AMPLIFIED BLADE) - Preferred
  
• BARRIER (ENERGETIC DEFENSE) - Preferred
  
• FIRE MINE (FLAMING ARRAY) - Enabled (with friendly fire off)
  
• ICE MINE (CHILLING ARRAY) - Enabled (with friendly fire off)
  
• FADE CLOAK (DECLOAKING BLAST) - Preferred
  
• REVIVAL (LIFE WARD) - Enabled

The builds in this guide should work on all difficulties, even Nightmare, if you take advantage of combos and gear appropriately. With that said, you might want to check my mate Desert Orchid 1's guide that's designed specifically for Nightmare