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Heidelun

Outer OneUpcomingKR SS

하이델룬

Flame of Freedom✦ Outer One
Rarity
Outer One
Element
Flame of Freedom
Faction
Unaffiliated
Class
Gunner
Voice Actor
Kang Su-jin
Unique Passive
System Heretic
Exclusive Weapon
Ex Nihilo
Ultimate
Unreal Black Hole
Original Korean Release Date
2025-07-08
Estimated Release Date
2026-11-03

Base Stats

Lv 1 · KR-server data · Physical
HP
466
ATK
196
M-ATK
84
DEF
26
RES
26

Unique Passive

System Heretic Passive

TierEffect NameEffect
First AcquisitionWhen you take fatal damage in a single hit while at 100% HP, you survive with 1 HP and enter Entropy Ghost (cooldown: 4). When you gain an action-control effect, you gain Sequence Break.
Entropy Ghost (duration 2) Cannot be removedCan attack enemies in Banish or Phase Leap state. This effect is treated as an action-control and Banish state, and cannot be targeted by skills or effects.
Sequence Break (duration 2) Cannot be removedAfter using a skill, gain an additional action and remove this effect.
Max AwakeningIf you have a debuff or are in Entropy Ghost state, critical hit chance increases by 30%. When you take fatal damage in a single hit while at 75% HP or higher, you survive with 1 HP and enter Entropy Ghost (cooldown: 3). If you would be banished, you enter Entropy Ghost state instead. When you gain an action-control effect, you gain Sequence Break.
Max ManifestationIf you have a debuff or are in Entropy Ghost state, critical hit chance and attack power increase by 30%. When you take fatal damage in a single hit while at 50% HP or higher, you survive with 1 HP and enter Entropy Ghost (cooldown: 2). If you would be banished, you enter Entropy Ghost state instead. When you gain an action-control effect, you gain Sequence Break. When hit by a skill-control effect or cooldown effect, reset the cooldowns of the 2 skills with the longest remaining cooldown.

Classes

TierClass
Tier 1Gunner
Tier 2Agent, Overrider
Tier 3L.T.K, Root Hacker, Chaos Blinger

Common Classes

Gunner+6 more → Tier 1 A basic class that uses a pistol to deal physical damage to enemies at range.

Reload

LvEffect
1Max bullets: 3. Basic attack/counter consumes 1 bullet. At the start of your team's turn, if bullets are 0, load Magic Bullet to max. Attacks that consume a bullet gain +5% critical hit chance. (Magic Bullet:: If consumed to deal damage, deal additional magic damage equal to 25% of attack power to that target. Can attack or use skills even with no bullets.)
2Max bullets: 3. Basic attack/counter consumes 1 bullet. At the start of your team's turn, if bullets are 0, load Magic Bullet to max. Attacks that consume a bullet gain +10% critical hit chance.

Agent+1 more → Tier 2 A skilled gunslinger who fights by creating advantageous situations through swift movement.

Agility

LvEffect
1Max bullets: 3. Basic attack/counter consumes 1 bullet. At the start of your team's turn, if bullets are 0, load Magic Bullet to max. Attacks that consume a bullet gain +20% critical hit chance. (Magic Bullet:: If consumed to deal damage, deal additional magic damage equal to 25% of attack power to that target. Can attack or use skills even with no bullets.)
2Max bullets: 3. Basic attack/counter consumes 1 bullet. At the start of your team's turn, if bullets are 0, load Magic Bullet to max. Attacks that consume a bullet gain +25% critical hit chance.

L.T.K+1 more → Tier 3 An advanced class that can flexibly eliminate both multiple targets and single targets with stylish movement.

Perfect Shot

LvEffect
1Max bullets: 3. Basic attack/counter consumes 1 bullet. At game start, gain the Perfect Shot 1 effect. At the start of your team's turn, if bullets are 0, load Magic Bullet to max. On enemy kill, gain 1 TP and gain the Perfect Shot 1 effect. (Magic Bullet:: If consumed to deal damage, deal additional magic damage equal to 25% of attack power to that target. Can attack or use skills even with no bullets.) (Perfect Shot 1: Cannot be removed: Attack power/critical hit chance +20%. This effect is removed when you take damage.)
2Max bullets: 3. Basic attack/counter consumes 1 bullet. At game start, gain the Perfect Shot 2 effect. At the start of your team's turn, if bullets are 0, load Magic Bullet to max. On enemy kill, gain 1 TP and gain the Perfect Shot 2 effect. (Magic Bullet:: If consumed to deal damage, deal additional magic damage equal to 25% of attack power to that target. Can attack or use skills even with no bullets.) (Perfect Shot 2: Cannot be removed: Attack power/critical hit chance +25%. This effect is removed when you take damage.)

Unique Classes

Overrider Tier 2 A special class that uses a pistol to infiltrate system flaws and overturn the common sense of battle.

Error Stack

LvEffect
1Max bullets: 3. Basic attack/counter consumes 1 bullet. At the start of your team's turn, if bullets are 0, load Magic Bullet to max. Apply Error Stack 1 effect to enemies you damage. (Magic Bullet:: If consumed to deal damage, deal additional magic damage equal to 25% of attack power to that target. Can attack or use skills even with no bullets.) (Error Stack 1: (stack 10 / duration 2): Attack power/spell power -3%. Received penetration damage +5%. When attacked, this effect's stacks and duration increase by 1. This effect is treated as a buff.)
2Max bullets: 3. Basic attack/counter consumes 1 bullet. At the start of your team's turn, if bullets are 0, load Magic Bullet to max. Apply Error Stack 2 effect to enemies you damage. (Error Stack 2: (stack 10 / duration 2): Attack power/spell power -4%. Received penetration damage +5%. When attacked, this effect's stacks and duration increase by 1. This effect is treated as a buff.)

Root Hacker Tier 3 An advanced class that uses a pistol to corrupt the system's core rules and erode enemies.

Paradox Worm

LvEffect
1Max bullets: 3. Basic attack/counter consumes 1 bullet. At the start of your team's turn, if bullets are 0, load Magic Bullet to max. When attacking enemies, damage dealt to the target increases by 5% per enemy buff. Gain Paradox Worm effect on enemies you damage. (Magic Bullet:: If consumed to deal damage, deal additional magic damage equal to 25% of attack power to that target. Can attack or use skills even with no bullets.) (Paradox Worm: (stack 10 / duration 2): Attack power/spell power -5%. Received penetration damage -10%. When attacked, this effect's stacks and duration increase by 1. This effect is treated as a buff.)
2Max bullets: 3. Basic attack/counter consumes 1 bullet. At the start of your team's turn, if bullets are 0, load Magic Bullet to max. When attacking enemies, damage dealt to the target increases by 10% per enemy buff. Gain Paradox Worm effect on enemies you damage.

Chaos Blinger Tier 3 An order-destroyer who uses a pistol and spreads chaos across the battlefield.

Digital Pandemic

LvEffect
1Max bullets: 3. Basic attack/counter consumes 1 bullet. At the start of your team's turn, if bullets are 0, load Collapse Bullet to max. When attacking enemies, increase damage the target takes by 10% per enemy debuff until end of turn. After attacking, if the target has a removable debuff, copy a debuff to 1 nearby enemy within 3 tiles. (Collapse Bullet: Darkness: If consumed to deal damage, deal additional magic damage equal to 25% of attack power to that target and apply a random debuff and Collapse. Can attack or use skills even with no bullets.) (Collapse: Darkness (duration 2): When attacked, explode dealing dark fixed damage equal to 25% of caster's attack power within a 1-tile radius.)
2Max bullets: 3. Basic attack/counter consumes 1 bullet. At the start of your team's turn, if bullets are 0, load Collapse Bullet to max. When attacking enemies, increase damage the target takes by 15% per enemy debuff until end of turn. After attacking, if the target has a removable debuff, copy a debuff to 1 nearby enemy within 3 tiles.

Skills

Common Skills

SkillTagsTPRangeCDEffect
Suppressing Fire+5 more →Ranged Directional Combat12-42 turnsConsumes 1 bullet. Fire the gun at an enemy to deal damage equal to 120% of attack power and apply Suppression for 1 turn. Suppression Skill Control (stacks 1): Cannot gain TP.
Armor-Piercing Reload+4 more →-1Self3 turnsImmediately after using the skill, can attack or use a skill again. Empty all remaining ammo and reload Armor-Piercing Rounds to max. Armor-Piercing Rounds: If consumed to deal damage, deal additional physical fixed damage equal to 25% of Attack to that target and remove 1 TP. Can attack or use skills even with no ammo.
Double Down+5 more →Ranged Directional Combat22-43 turnsConsumes 2 bullets. Fire the gun at an enemy to deal damage equal to 80% of attack power. Fire one more shot to deal damage equal to 50% of attack power.
Tactical Maneuver+1 more →TP Removal11-13 turnsDesignate a direction and move up to the farthest empty tile within 4 tiles ahead, stealing TP along the way. If the stolen TP is 0, get TP back and this skill's cooldown is reduced by 1. Immediately after using the skill, you can additionally attack or use a skill.

Unique Skills

SkillTagsTPRangeCDEffect
Override Field-1Self2 turnsImmediately after using this skill, you can take an additional attack or use a skill. Gain the Override Field effect for 2 turns. Override Field Cannot be removed (duration 2): Ignore elemental advantage/disadvantage. Ignore attack/defense-type advantage/disadvantage. Damage you deal to all enemies increases by 50% as if you had advantage, and damage you take decreases by 50%.
Terminal ProtocolRanged Combat12-42 turnsConsumes 1 bullet. Deal 140% of attack power to an enemy, plus an additional 20% of attack power per buff the target has. This skill is not affected by cover and cannot be guarded against. If the enemy is not killed by this skill, banish it for 1 turn. Banish+1 more → Cannot be removedAction ControlBanish (duration 1): Unaffected by normal damage, skills, or effects, and cannot act.
Astral BladeElectric Ranged Directional31-13 turnsChoose a direction and deal 90% of attack power to enemies in range and inflict Shock. Additionally apply 1 random effect from Collapse, Daze, Suppress, or Banish. Collapse Darkness (duration 2): When attacked, explode dealing dark fixed damage equal to 25% of caster's attack power within a 1-tile radius. Shock Action ControlElectric (duration 2): Cannot counter. Daze Action ControlMovement Control (duration 2): Movement -2. Cannot take additional movement or additional actions. Cannot guard. Suppress Skill Control (duration 1): Cannot gain TP. Lasts 1 turn. Banish+1 more → Cannot be removedAction ControlBanish (duration 1): Unaffected by normal damage, skills, or effects, and cannot act.
Null SpreadRanged Directional21-13 turnsConsumes all bullets. Empty all remaining bullets and load Magic Bullet to max. Choose a direction and fire at any targetable enemy in a straight line within range, dealing 30% of attack power as damage. Repeat until all bullets are consumed or the enemy is killed. ---

Ultimate

Unreal Black Hole Ultimate Darkness Ranged Position Control

Quote: "There's nothing left for me in this world...! Cosmos data hack complete. Transmitting target data! You won't survive...! Disappear!!"

TierEffect NameEffect
First AcquisitionOn use, lose 50% of remaining HP and gain 10% increased attack power until the start of your next turn. Target a location and deal 100% of attack power to enemies within a 3-tile radius around the target, pulling them toward the center.
Max AwakeningOn use, lose 50% of remaining HP and gain 25% increased attack power until the start of your next turn. Target a location and deal 120% of attack power to enemies within a 3-tile radius around the target, pulling them toward the center.
Max ManifestationOn use, lose 50% of remaining HP and gain 50% increased attack power until the start of your next turn. Target a location and deal 150% of attack power to enemies within a 3-tile radius around the target, pulling them toward the center.
  • CostTP 5Range1-4AreaAoECooldown5 turns

Manifestation Skill - Outer One

Entropy Ghost Penetration

TierEffect NameEffect
First AcquisitionOn use, lose 10% of max HP. Enter Entropy Ghost state.
Max ManifestationOn use, lose 10% of max HP and recover 1 TP. Remove all debuffs on yourself and enter Entropy Ghost state.
Entropy Ghost (duration 1) Cannot be removed Action ControlCan attack enemies in Banish or Phase Leap state. This effect is treated as an action-control and Banish state, and cannot be targeted by skills or effects.
  • CostTP -RangeSelfAreaAoECooldown4 turns

Manifestation Artifacts

Overload Loader+4 more → More! Stronger! Enhances the wearer's firearm to neutralize enemy defenses and load more bullets.

LvEffect
1Physical penetration +15%. Max bullets +1.
2Physical penetration +30%. Max bullets +1.
3Physical penetration +45%. Max bullets +1.
4Physical penetration +60%. Max bullets +1.

Initial Armor-Piercing Magazine+2 more → Prepares the wearer in optimal condition to gain a strong advantage from the opening engagement.

LvEffect
1Start the game with Armor-Piercing Bullet loaded. Armor-Piercing Bullet: If consumed to deal damage, deal additional physical fixed damage equal to 25% of attack power to that target and remove 1 TP. Can attack or use skills even with no bullets.
2Critical hit chance +10%. Start the game with Armor-Piercing Bullet loaded.
3Critical hit chance +20%. Start the game with Armor-Piercing Bullet loaded.
4Critical hit chance +30%. Start the game with Armor-Piercing Bullet loaded.

Wind Step+10 more → Makes the wearer's steps as light as the wind, improving movement speed and causing enemies' critical attacks to miss.

LvEffect
1At end of action, gain Wind Step 1 effect. Wind Step 1: Movement +1 (does not stack). Received critical hit chance -10%. Max 2 stacks. Removed after being attacked.
2At end of action, gain Wind Step 2 effect. Wind Step 2: Movement +1 (does not stack). Received critical hit chance -15%. Max 2 stacks. Removed after being attacked.
3At end of action, gain Wind Step 3 effect. Wind Step 3: Movement +1 (does not stack). Received critical hit chance -20%. Max 2 stacks. Removed after being attacked.
4At end of action, gain Wind Step 4 effect. Wind Step 4: Movement +1 (does not stack). Received critical hit chance -25%. Max 2 stacks. Removed after being attacked.

Sunset Pendant (Exclusive) A sunset-colored pendant that Heidelun keeps close to her chest. Thanks to the sparkling crimson gem in the center, it looks like a burning sunset.

  • HP +30%. If you have a shield, physical penetration increases by 30% and you gain Cover state. At the start of your team's turn, if HP is 50% or below, gain Safety Barrier effect equal to max HP for 2 turns. (Cooldown 2)
  • Cover: Cannot be critically hit by enemy directional attacks, and misses occur reducing damage taken by 50%.
  • Safety Barrier: HP-proportional shield. Cannot be removed.

Artifacts

Overload Loader+4 more →: "More! Stronger! Enhances the wearer's firearm to nullify enemy defense and load more bullets."

LvEffect
1Physical Penetration +15%. Max bullets +1.
2Physical Penetration +30%. Max bullets +1.
3Physical Penetration +45%. Max bullets +1.
4Physical Penetration +60%. Max bullets +1.

Initial Armor-Piercing Magazine+2 more →: "Prepares the wearer in optimal condition to gain a strong advantage from the very first engagement."

Initial AP Magazine+1 more →

LvEffect
1Start the game with AP Bullet loaded. AP Bullet: if consumed to deal damage, deals additional physical fixed damage equal to 25% of attack to that target and removes 1 TP. Can attack or use skills even without bullets.
2Crit Rate +10%. Start the game with AP Bullet loaded.
3Crit Rate +20%. Start the game with AP Bullet loaded.
4Crit Rate +30%. Start the game with AP Bullet loaded.

Wind Step+10 more →: "Makes the wearer's steps light as wind, increasing movement speed and causing enemy critical attacks to miss."

LvEffect
1On action end, gain Wind Step 1 effect. (Wind Step 1: Movement +1 (does not stack). Received Crit Rate -10%. Max 2 stacks. Removed after being attacked.)
2On action end, gain Wind Step 2 effect. (Movement +1 (does not stack). Received Crit Rate -15%. Max 2 stacks. Removed after being attacked.)
3On action end, gain Wind Step 3 effect. (Movement +1 (does not stack). Received Crit Rate -20%. Max 2 stacks. Removed after being attacked.)
4On action end, gain Wind Step 4 effect. (Movement +1 (does not stack). Received Crit Rate -25%. Max 2 stacks. Removed after being attacked.)

Sunset-Light Pendant [exclusive] - A sunset-light pendant Heidelloon keeps deep in his bosom. The scarlet gem in its center glitters, making it look like a burning sunset.

LvEffect
EffectHP +30%. If holding a shield, Physical Penetration increases by 30% and gains Cover state. At ally turn start, if HP is 50% or below, gain Safety Barrier effect equal to max HP for 2 turns. (Cooldown 2) • Cover: Cannot be crit by enemy directional attacks; glancing hits occur, reducing received damage by 50%. • Safety Barrier: HP-proportional shield. Cannot be removed.

Signature Gear

Ex Nihilo
Ex Nihiloweapon · Pistol · Outer One · Heidelun exclusive

KR release · gmap.gg

The pistol used by the last captain of Adelun. It absorbs the user's spiritual energy to unleash overwhelming destructive power, and can self-destruct if the recoil cannot be withstood. When equipped by Heidelun, the weapon's full potential is unleashed.

6★
Stats
Max HP +122, ATK +382
Additional
ATK +20%, Crit Rate +20%

Aftershock (Exclusive). At the start of the game, the wearer's Max Ammo Count increases by 2. After attacking enemies, apply Kill Order 6 to a random 2 of the damaged enemies and gain Aftershock 6. When Aftershock 6 kills an enemy, Aftershock 6 triggers once more.

  • Kill Order 6: Crit Damage taken +20%. When taking lethal damage, the enemy that dealt it gains 1 TP and this effect is removed. Lasts 2 turns.
  • Aftershock 6: At the end of the character's turn, fire at the lowest-HP enemy within Range, dealing damage equal to 80% of ATK. Aftershock 6 triggers even without ammo. Lasts 1 turn. Cannot be dispelled.

Kill Order (General). After attacking enemies, apply Kill Order 6 to a random 1 of the damaged enemies. (Cooldown 1 turn)

  • Kill Order 6: Crit Damage taken +20%. When taking lethal damage, the enemy that dealt it gains 1 TP and this effect is removed. Lasts 2 turns.
System Heretic Setarmor · Medium · Outer One

Heidelun's self-motif Outer One armor set (paid).

2-set: Physical Penetration +15%, Critical Chance +15%.

4-set: On attacking an enemy, Attack +30%; when dealing lethal damage, once per turn gain a shield equal to 50% of Max HP for 2 turns.

Note. No accessory or rune is exclusive to Heidelun; the guide recommends the Ancient Hero's Ring accessory for attack-power scaling.

Guide

Overall: An even stronger but more fragile ultra-burst glass cannon. A more extreme upgrade of Christian: durability got even more frail while firepower got even stronger, and with a single skill click he can gain type advantage against all attributes/troop types, greatly increasing solo-all-kill potential. Depending on class choice he can be run as an extreme counter to buff-stacking parties, or actively apply debuffs for equivalent returns, allowing flexible operation. Achieving Manifestation 1+ lets him actively enter the "Entropy Ghost" state, projecting overwhelming firepower one-sidedly while invincible (even if only for 1 turn), which is extremely powerful. A high-Manifestation, high-awakening exclusive-weapon Heidelloon in the arena can Ghost -> Tactical Maneuver for TP 2 -> Blackhole to slash the whole party's HP, then sweep with follow-up Aftershock, and even if the opponent survives, he is in Entropy Ghost state so nothing can touch him unless it is another Entropy Ghost Heidelloon. Everything (awakening/manifestation, weapon awakening, exclusive armor) is designed so he grows honestly in proportion to money spent; judge the right line for yourself.

Passive: A passive that forces him to be a glass cannon. Heidelloon has enormous attack plus a Christian-era trait that attacks again on enemy kill, so the Entropy Ghost state (which secures survival and crit rate at once) is very strong. He can attack banished/Entropy Ghost enemies, so in PVP it is the only way to kill an enemy Entropy Ghost Heidelloon. Absolutely avoid raising his HP and defense. Manifestation adds attack boost and converts the Banish state into Entropy Ghost, letting him counter Diablo's Phantom Walk, Joan's bind, etc. In high-difficulty dungeons (challenges, late simulation training) where enemy gunners fire banish-bullets, a high-Manifestation Heidelloon becomes stronger when banished, so he counters banish-bullet gunners.

Classes: The Tier-3 options are Root Hacker (buff counter), Chaos Blinger (debuff counter), and L.T.K. Root Hacker is recommended as 1st-priority raise and endgame class: its Paradox Worm (buff-treated debuff, max 10 stacks) applies easily (2 stacks per hit, ~4 stacks in 1 turn with the exclusive weapon's double attack), and its damage-amp scales with buff count so Paradox Worm counts toward it too; its "penetration damage taken" increase also supports penetration-type allies (i.e. Joan). Warning: synergy with Black Prince's Atomic Blast (which wipes buffs and blocks new buff gain) is the worst, since Paradox Worm is a removable buff and cannot be applied to enemies under the Despair debuff; Isabel's exclusive Longinus can also wipe buffs from 5-awakening, and buff-steal units like Silver can steal this debuff, so combine carefully. Chaos Blinger is the debuff counter: actively applies many debuff types, fires Collapse Bullet for area dark damage, and its contagion spreads debuffs, so it excels vs Fierce-Battle Raid / World Boss Raid (debuff-heavy, buff-scarce) and synergizes well with Black Prince's Death Lord (which spreads Loss-of-Will debuffs). L.T.K. (max bullets 4, only class with base movement 4, most mobile) starts stages with the infinite "Perfect Shot" buff (+25% attack/crit at max) and gains 1 TP on kill, but the buff evaporates on taking any damage, so it is weak in raids like Cerberus/Diene where you cannot kill and cannot avoid damage; lowest raise priority since Root Hacker has better damage-amp and a separate class tree.

Core skills & Ultimate:

  • Override Field: TP 1, gain the unremovable 2-turn buff granting type-advantage vs all enemies (+50% damage dealt, -50% damage taken), plus a follow-up action; cooldown 2. Called a "balance-breaking" skill.
  • Terminal Protocol (main damage skill 1): TP 2, 1 bullet, 140% + 20% per enemy buff, ignores cover/escort, banishes if it fails to kill; cooldown 3. Great with Entropy Ghost (can follow up).
  • Astral Blade: TP 3, 3x5 area, 90% electric damage + Shock + 1 random debuff; cooldown 3. Does not consume bullets (so no Magic-Bullet/Collapse-Bullet amp), random debuffs, but wide range helps his poor mobility; good class-passive synergy for Chaos Blinger (applies 2 debuffs).
  • Null Spread (main damage skill 2): TP 2, empties all bullets and reloads Magic Bullets to max, then fires down a straight line at 30% per shot (each shot's real multiplier becomes 55% with Magic Bullet, so ~155% start), repeating until bullets run out or enemy dies; cooldown 3. With L.T.K. + exclusive weapon (6-bullet magazine, full awakening) the peak reaches 430%; but only ~220% on other classes with a stand-in weapon, sometimes weaker than Terminal Protocol. Cannot fire Collapse Bullets via Null Spread.
  • Tactical Maneuver: TP 1, move to farthest empty cell within 4 front cells, steal TP from passed enemies (if 0 stolen, refunded and cooldown -1), plus follow-up action; cooldown 3. Useful for his slow (movement 3) main classes; with TP steal, a 1-turn instant Blackhole is possible if 3 enemies are lined up.
  • Unreal Blackhole (Ultimate): dark area attack targeting within 4 cells; on use lose 50% of remaining HP and gain +15% attack until next turn start, then deal 100%~120% damage to enemies within 3 rings around the target and pull them to center (position control). Wide range, all passives apply, first-strike boost. Risky (halves HP, blocks passive-trigger condition), so normally use carefully; but firing while in Entropy Ghost is near no-risk since invincible, and after obtaining the manifestation skill he can fire it freely; full-manifestation drops the passive condition to 50% so HP loss barely matters. Grows in power/convenience the more you pay.
  • Manifestation skill Entropy Ghost: no TP, pays 10% HP to grant self Entropy Ghost; triggers Sequence Break for a re-action. First enhance adds debuff removal, second enhance adds 1 TP charge; cooldown 4. Effectively pays HP for 1-turn invincible + crit rate, lasting until end of the next turn's action (up to 2 Ghost attacks) plus a re-action. In PVP (as of mid-2025) the only counter to a Manifestation-1+ Heidelloon is another Manifestation-1+ Heidelloon, so this skill is considered essential for active PVP players.

Exclusive weapon & recommended gear: Weapon is Ex Nihilo; extra stats attack + crit, max bullets +1~2.

  • Kill Order: applied to a random hit enemy after attacking; received crit damage +10~20%; if that enemy takes lethal damage, the dealer gains 1 TP and Kill Order is removed; lasts 2 turns. 1 target, becomes 2 from 5-awakening.
  • Aftershock (Heidelloon-exclusive): on action end, fire at the lowest-HP enemy in range for 50~80% damage; triggers even without bullets; if it kills, Aftershock triggers once more (no cap on repeats, theoretically can wipe all enemies in 1 turn). Essentially mandatory; awakening's crit-multiplier rise contributes greatly to firepower. Note: Aftershock is not an "extra attack," so whetstones are meaningless.
  • Armor: Ignore survival entirely, go full-burst; unlike Christian there is no crit benefit and most is attack-multiplier, so pile everything into attack. Best Legendary armor is the Assassin 4-set; One-Man-Army 4-set + physical penetration can counter PVP crit-damage-reduction tank meta. Heroic: Chivalrous 4-set, or Chivalrous 2 + Slayer 2 for attack 20%. The self-themed "System Heretic" set (2-set: physical pen 15% + crit 15%; 4-set: attack +30% on enemy attack, plus once-per-turn 2-turn shield of 50% max HP on dealing lethal damage) is a broken paid-item set worth considering if wealthy.
  • Accessories: attack-focused, so the standard Ancient Hero's Ring is recommended (though it slightly raises survival, making passive-trigger a bit harder). Arrowhead valid if crit + Terminal Protocol focus, but note it does not apply to Null Spread. Heroic: Wound-Worsening Charm for attack, or Golden Dice for crit. Fang usable for attack but physical pen applies only to combat attacks, so unsuitable if Astral Blade/Null Spread are main; whetstones meaningless since Aftershock is not an extra attack.

No explicit S/A/B tier letter rating is present in the text.

Awakening/Manifestation progression: Manifestation resource: Error Cube. - Stage 1: Gain Entropy Ghost. Ultimate Enhancement 1. - Stage 2: Passive Enhancement 1. Stat Enhancement. - Stage 3: Active Enhancement 1. Artifact acquired: Overload Loader, Initial Armor-Piercing Magazine, Wind Step. Ultimate Enhancement 2. - Stage 4: Passive Enhancement 2. Artifact Enhancement 1. - Stage 5: Active Enhancement 2. Artifact Enhancement 2. Ultimate Enhancement 3. - Stage 6: Passive Enhancement 3. Artifact Enhancement 3. Exclusive Artifact acquired: Sunset-Light Pendant.

KR Creator Guide

Character review of Heidelun by 하막군의게임튜브 · 2026-08-04

The second Outer One, released for the 1.5-year anniversary, and the reviewer thinks Heidelun came out stronger than Black Prince. His assessment is unusually stark: at the time of filming his guild had found essentially no answer to him. If Heidelun moves first, walks in and opens fire, the team dies — the only counters he can name are a Mingming Sanctuary or playing around revives. (19:04)

Entropy Ghost is the whole survival plan

Above 75% HP, a single lethal hit leaves him at 1 HP in Entropy Ghost instead of killing him. Banishment does the same. Ghost behaves like Banish except he can still move and attack, and because Ghost is itself an Action Control effect it automatically grants Sequence Break — so he gets an extra action out of it. (1:00)

That gives you the one reliable way to kill him: multi-hit skills. Because the trigger needs a single lethal blow from above 75% HP, anything that chips him down in several instances never qualifies, and he dies normally. Suppressing Fire and similar multi-hit attacks are what he recommends. (2:34)

The Outer One skill Entropy Ghost runs on its own cooldown, separate from the passive trigger, so using one doesn't lock out the other. (3:05)

Class: Chaos Blinger or L.T.K to attack, Root Hacker to grind

Root Hacker loads Magic Bullets and applies Paradox Worm on hit: -5% ATK and M-ATK per stack and +10% penetration damage taken per stack, up to 10 — so up to +100%. Shooting applies two stacks at a time because the shot and the round both land. (3:36)

The important quirk, and he demonstrates it on camera: Paradox Worm counts as a buff, despite showing a debuff icon. Black Prince's Atomic Blast+1 more → wipes it, and because Atomic Blast also blocks buff acquisition, shooting afterwards doesn't restack it. (4:38)

Chaos Blinger loads Collapse rounds instead — 25% fixed damage in a ring around each affected target, so several tagged enemies detonate together. It raises damage taken by 15% per debuff on the target until his own turn ends, which the reviewer confirms means it boosts his weapon's Aftershock chain but nothing your other units do. Attacking with an area skill also copies debuffs outward across the field. (5:36)

He expects most attacking players to run Chaos Blinger or L.T.K+1 more →. (7:10)

The skills

SkillTagsTPRangeCDEffect
Override Field-1Self2 turnsImmediately after using this skill, you can take an additional attack or use a skill. Gain the Override Field effect for 2 turns. Override Field Cannot be removed (duration 2): Ignore elemental advantage/disadvantage. Ignore attack/defense-type advantage/disadvantage. Damage you deal to all enemies increases by 50% as if you had advantage, and damage you take decreases by 50%.
Terminal ProtocolRanged Combat12-42 turnsConsumes 1 bullet. Deal 140% of attack power to an enemy, plus an additional 20% of attack power per buff the target has. This skill is not affected by cover and cannot be guarded against. If the enemy is not killed by this skill, banish it for 1 turn. Banish+1 more → Cannot be removedAction ControlBanish (duration 1): Unaffected by normal damage, skills, or effects, and cannot act.
Astral BladeElectric Ranged Directional31-13 turnsChoose a direction and deal 90% of attack power to enemies in range and inflict Shock. Additionally apply 1 random effect from Collapse, Daze, Suppress, or Banish. Collapse Darkness (duration 2): When attacked, explode dealing dark fixed damage equal to 25% of caster's attack power within a 1-tile radius. Shock Action ControlElectric (duration 2): Cannot counter. Daze Action ControlMovement Control (duration 2): Movement -2. Cannot take additional movement or additional actions. Cannot guard. Suppress Skill Control (duration 1): Cannot gain TP. Lasts 1 turn. Banish+1 more → Cannot be removedAction ControlBanish (duration 1): Unaffected by normal damage, skills, or effects, and cannot act.
Null SpreadRanged Directional21-13 turnsConsumes all bullets. Empty all remaining bullets and load Magic Bullet to max. Choose a direction and fire at any targetable enemy in a straight line within range, dealing 30% of attack power as damage. Repeat until all bullets are consumed or the enemy is killed. ---

Gear

The System Heretic set, or Black Crow without it. One Against a Thousand is also fine if you want the Physical Penetration. Accessory: his exclusive if you have it, otherwise Black Banner is plenty. (13:11)

The weapon is mandatory

Aftershock is the reason. After attacking he fires again; if that kill lands, he fires again; and again, until nothing dies. He initially read the text as one extra shot and confirms in play that it is unbounded. It scales from 50% of ATK at base to 80% at full awakening, and he says guild-battle Heidelun simply kills whole teams with it.

★3 raises his ammo count to 2, ★5 applies Kill Order to two targets rather than one. Take at least one copy of the weapon — this is not optional. (13:52)

Runes

He runs a full Time set. Without it, Chaos and Ultimate mixed is fine — most players just run Time. (15:25)

Manifestation: 5 is the number

2 adds ATK. 4 adds ATK and, notably, resets the two longest cooldowns when he is hit by a Skill Control or cooldown effect — he calls this the direct answer to Este Dode decks. 6 pushes ATK to +30% and drops Entropy Ghost's cooldown to 2, i.e. a revive every other turn.

But 5 is the breakpoint that changes how he plays: Entropy Ghost starts returning 1 TP. Override Field then Entropy Ghost puts him back to 3 TP, which funds an Astral Blade in the same turn. (15:56)

Artifact: the exclusive, and it isn't close

Overload Loader+4 more →, Initial Armor-Piercing Magazine+2 more → and Wind Step+10 more → are all filler in his view — Overload Loader is what most non-full-manifestation players will use.

Sunset-Light Pendant is the real one: +30% Max HP on a character with a very low health pool, Physical Penetration and a cover state while shielded, and a Safety Barrier worth his Max HP at turn start below 50%. That barrier is what pays for the ultimate's self-damage, and it also refills him the turn after Entropy Ghost drops him to 1 HP. It cannot be removed. (17:29)

Our write-up of the video above, not a transcript — the reviewer’s own findings and opinions, put into English against Heidelun’s kit and linked up to the rest of the wiki. Timestamps open the original at that moment.

Reworks

KR-server balance changes for this unit, newest first (see the full Rework History).

Outer One2026-07-07

Balance improvements for Outer One grade characters

  • Unique passive [System Heretic] reworked across all awakening and manifestation tiers.
  • Added: if banished, become Entropy Ghost instead; gaining an action-control effect now grants Sequence Break.
  • Entropy Ghost now ignores the 'cannot gain re-action' restriction and counts as action-control/banished.
  • Tier 3 awakening: lethal-damage revive Cooldown reduced 4 to 3, and now triggers at 90/80/75% HP thresholds.
  • Tier 4-6 awakening: Crit Rate +10/20/30% while holding a debuff or in Entropy Ghost.
  • Manifestation tiers add ATK +10/20%; tier 4 also resets the Cooldowns of the 2 longest-Cooldown skills when hit by a skill-control or cooldown effect.
Genesis War Mobile 2.5th Anniversary Update Notice ↗

Trivia

Release Date

Original Korean release: 2025-07-08. Released for the 1.5th anniversary as the 2nd Outer One.

Estimated global release: 2026-11-03.

KR Banner History

Korean-service banner runs for this unit, newest first (see all runs on KR Banner History).

2026-07-07 → 2026-08-11 · 5 weeksSelection
2025-07-08 → 2025-08-05 · 4 weeksDebut
Stats, skills, and art for Heidelun are translated and adapted from its NamuWiki page, licensed under CC BY-NC-SA 2.0 KR, with additional KR-server data from gmap.gg. Genesis War Mobile and its characters are property of their respective rights holders.