Detailed analysis of hero skill usage (and lack of) can be found at Hero behavior/Unexpected behavior.
 Influencing hero behaviour
 Combat modes
Heroes will aggressively confront enemies:
- They will attack (in priority order) called targets, selected targets within spirit range of the hero, non-selected enemies actively engaged with the party, and non-selected enemies within the hero's aggro range.
- They will separate from the party, as necessary.
Heroes will guard the area near a flag or the controlling player (whichever is closer and within earshot), refraining from combat until actively engaged.
- They will not attack enemies unless forced to use a skill, the selected target is called, the selected enemy actively engages the party, or the non-selected enemy enters the party's aggro circle.
- They will not move beyond the guarded area unless forced to use a skill and the target is out-of-range.
- They will return to the guarded area after using a forced skill or the enemy moves far beyond the area.
- They will often go out of their way to attack a spirit, despite being in "Guard Mode".
 Avoid Combat
Heroes never attack and will attempt to avoid enemies when attacked, kiting as needed. They will not attack selected or called targets unless forced to use a skill.
- They generally will not use skills that directly target foes or cause point blank area of effect damage.
- They will use skills that indirectly affect the enemy:
 Forced skill use
- Heroes can be ordered to execute skills by clicking on the appropriate skill on the hero skill bar.
- When a hero is ordered to execute a skill during the activation of another skill, the hero will cancel the activation of that skill and proceed with the ordered skill.
- The hero will not use any other skills until it successfully activated the ordered skill.
- Locking a target
- Heroes can be ordered to drop their current bundle by clicking on their monitor.
 AI capabilities and limitations
 AI knowledge
- Heroes can "read" health bars, and can detect the presence of hexes, conditions and enchantments.
- Heroes know about all active effects. They will not try to apply an enchantment, hex, condition or weapon spell on someone who is already affected by the same enchantment, hex, condition or weapon spell.
- Heroes can detect party members' energy, as they will not use skills such as Blood Ritual on characters with full energy pools.
- Heroes can detect enemy skill activation, and will only use interrupts which are appropriate to the skill type. They have no reaction time; their interrupts are never late.
Heroes do not coordinate their actions with each other. This may result in redundant skill usage. For example:
- Multiple heroes with resurrection skills may attempt to resurrect the same fallen party member; the fastest one will succeed (unless interrupted), which means the others will have wasted energy and time.
- Multiple heroes may try to heal the same ally, even if it's almost at full health, or damage the same foe, even if it's almost dead.
- They may try to remove the same hex, condition, or enchantment. They may try to interrupt the same skill.
- Heroes have no concept of the danger of hexes and condition, or the usefulness of enchantments. They will remove these seemingly at random.
- Heroes have no concept of the strength of a skill. They will not prioritize any skills for interruption.
- All heroes with resurrection skills will attempt to resurrect fallen party members; the fastest one will succeed (unless interrupted), which means the others will have wasted energy and time.
- Healers often attempt to resurrect in mid-combat. Players that want their healers to focus on healing should give resurrection skills to non-healers, or manually disable the healer's resurrection skills to reserve them for the player's discretion.
- Heroes will not always line up ranged characters at the rear, with melee characters in front, as you might expect.
- Heroes will change formation when the player changes from a melee weapon to a ranged or a ranged weapon to a melee.
- Heroes holding bundle item will stand in the front with melee characters.
 Default skill usage
- AI won't pre-cast Avatars before engaging into combat, as only the player can know when they are about to engage foes. Heroes will activate it soon after hitting their first foe. This behavior combined with the 2 second cast time could cause the hero to be interrupted. Once a battle ends, they won't re-cast it to keep maintained indefinitely.
 Binding rituals
- Except for Life, AI does not use passive spirits outside of combat. Spirits like Union will only be cast after a party member has already taken damage, but never to prevent that first strike.
- AI will place spirits wherever they happen to be, it is not programmed to make spirit walls as players would. Thus, it will use skills like Armor of Unfeeling, Signet of Creation, Signet of Ghostly Might, Spiritleech Aura once it detects the presence of a single spirit within range. Worry not, such skills have short recharge time and by the time it uses them again, the benefit will certainly be better as expected.
 Condition removal
- NPCs will try to cleanse allies of conditions, even if those conditions are about to wear off. This both wastes energy and delays party movement.
- They are better at detecting conditions than humans, who need to watch health bars or wait for other players to ping their effects (or mention them via chat).
- They will remove conditions on allies even when the other NPC wold benefit from the condition, e.g. Melandru's Resilience, or when unavoidable e.g. Cultist's Fervor.
 Condition spreading
- NPCs do not spread conditions. For example, while Apply Poison is active, they will not attack multiple targets to poison several foes. Worse, they will cease attacking poisoned foes if that preparation is active.
- Heroes seem to use an echo early in the fight, after that they will use a random skill depending on their situation, having no thought of what skill will be echoed.
- Battery skills
- NPCs will only use Blood Ritual/Blood is Power on martial profession allies that are holding a bundle or a caster weapon; even then, they wait until energy drops to 20 or less before casting.
- They will use these skills on caster allies regardless of their weapon type, but wait to cast until the target's energy drops to ~30 energy or less.
- NPCs will activate conjure spells based on their weapon’s current damage type, but ignore effects that change the damage (e.g. Winter or Staggering Force).
- Doublecast enchantments
- NPCs will wait to cast until foes are in range of both the caster and target ally. Unless foes are in its range it causes the bearer to close in by breaking formation. [verification requested]
- Enchantment removal
- NPCs will use use maintained enchantments during combat, but dismiss them afterward in order to regenerate energy. To force heroes to maintain such effects, you have to micromanage their usage: disable the skill (via
shift + click) and then manually cast (by clicking on the skill). To force the hero to use a skill on a specific ally, first select the ally in the party panel, then micro the skill as above.
- After casting a glyph, NPCs will prioritize skills optimized to the specified effect. For example, after invoking a Glyph of Lesser Energy, they will often ignore spells that cost only 5 in favor of those costing 15 or more.
 Healing and protection
- NPCs reserve party-wide healing skills (e.g. Heal Party) until multiple party members require healing.
- They prioritize the ally with the lowest health and will not protect goal-critical non-party NPCs (e.g. Prince Rurik or Master Togo). Players can micromanage this choice by targeting the ally.
- They cast hex-removal skills indiscriminately, regardless of danger level.
- NPCs will detect near-death allies and prioritize their healing.
- NPCs will not use protection skills in advance of a battle; players must micromanage pre-casting of skills such as Shelter.
- When allies are suffering from health degeneration, NPCs will use skills that reduce direct damage to no effect, for example casting Spirit Bond to counter Conjure Nightmare.
- NPCs will first use resurrection skills on dead allies that also posses resurrection skills.
- Multiple NPCs will attempt to resurrect the same ally.
 Hex removal
- NPCs prioritize cleansing over other considerations:
- They will remove minor hexes from allies that might enjoy a net benefit, e.g. removing Overload from a target under the effects of Resilient Weapon.
- After a battle is over, NPCs will take time to remove hexes (regardless of danger level), resulting in their being separated from the rest of the party. This makes it more difficult to avoid other foes in the area or along the party's route.
- NPCs do not prioritize threat levels. They will interrupt Flare on a current enemy even if a nearby foe is casting Rodgort's Invocation.
 Item spells
- Heroes will try to maintain defensive item spells when out of combat. They will attempt to follow foes when other allies are attacking. They will not drop item spells that cause offensive effects to use other offensive item spells.
 Nature rituals
- Heroes will try to keep Beast Mastery and Wilderness Survival spirits active at all times. Favorable Winds will only be used when in combat.
- NPCs maintain preparations outside of combat, even if no combat is imminent.
 Shadow steps
- NPCs will use prioritize the use of shadow steps to close distance to foes, sometimes ignoring or wasting the secondary effects. However, they will use Death's Charge to heal themselves while in melee range of their target.
- They will use shadow steps differently on different types of targets. For example, on the Isle of the Nameless, heroes will step to the Master of Healing (a caster) but walk/run to the Master of Lightning (a martial profession) and reserve Death's Charge as a self-heal.
- After using a shadow step, NPCs will sometimes walk away from a foe (and back towards the party).
- Heroes will only use shouts when in combat.
- They will only use "Make Haste!" on player characters and never on NPC allies.
- NPCs will use AoE spells on single targets, e.g. Earthquake against an animal.
- To maximize the effects of use of Point-Blank AOE damage skills, they will rush into combat, even if the rest of their build is not suited for close-combat. In particular, they will not reserve PBAoE skills to break aggro, e.g. they will also move close to foes to use Whirlwind, rather than using it to escape from that same foe.
 Touch skills
- NPCs with martial professions use touch skills efficiently, since they are already face to face. However, casters will break formation, rushing into to the frontline to cast such skills, risking their own safety. For example, Danika will use Healing Touch instead of remaining safely behind.
 Wards and Wells
- NPCs will invoke Wards and Wells when engaged in combat, regardless of the benefits. For example, they will cast Ward of Stability even if there is no risk of knock down.
- They do not pay attention to existing areas of effect, moving outside of beneficial effects to kite or remain within negative ones if they are not under direct attack.
- After the end of a battle, NPCs with both minion and well skills sometimes choose to invoke wells (even if they serve no purpose) instead of creating more minions.
 Weapon spells
- NPCs will cast offensive weapon spells on attacking allies appropriately, e.g. using Splinter Weapon on allies wielding martial weapons.
- However, they will overwrite those skills with supportive ones, especially on allies at critical health levels. For example, they will use Weapon of Warding, even if they just used Splinter Weapon on the same target.