Home News Complete Arcane Lineage Boss Guide – How to Beat Them All

Complete Arcane Lineage Boss Guide – How to Beat Them All

Author: Anthony Aug 07,2025

In Arcane Lineage, boss battles range from solo-able encounters for new players to epic team-based challenges requiring coordinated strategies and patience. Each boss presents unique mechanics, demanding careful planning and execution. The rewards are well worth the effort, however, as defeating these bosses yields some of the game's most coveted loot and powerful items. This guide will prepare you for the ultimate tests of skill.

Boss	Location	Difficulty
King Slime	Around the City	Easy
Yar’thul, the Blazing Dragon	Inside Mount Thul	Normal
Thorian, the Rotten	Deep in the Cess Grounds	Hard
Mettrom’s Vessel	Deeproot Canopy	Very Hard
Seraphon	Unlocked by ranking up in the Church of Raphion	Hard
Arkhaia	Unlocked by ranking up in the Cult of Thanasius	Very Hard

King Slime Location

King Slime spawns after 100 Slimes are defeated on the server. It will appear near the city closest to the last slain slime's location. A notice on the Quest Board will announce the King Slime quest, which consists of two steps: Find King Slime and Kill King Slime. This quest has a 30-minute global server cooldown.

King Slime Fighting Strategy

King Slime starts with 400 HP (600 HP if Corrupted), the lowest of any boss. Its main attack involves summoning more Slimes, which can overwhelm players if not dealt with quickly. It also uses area-of-effect (AOE) poison attacks. Bring potions and cleansing abilities. Its low health makes the battle straightforward: eliminate the summoned Slimes first, then focus on King Slime.

Attacks	Energy Cost	Effect
Slime Creation	1	Summons a Slime to fight for King Slime.
Crush	0	King Slime lunges forward, attacking a party member.
Poison Eruption	2	King Slime throws out a burst of Acid, poisoning your party. This attack cannot be dodged or blocked.
Scalding Spray	3	King Slime erupts with boiling hot liquid, poisoning your party. This attack cannot be dodged.

King Slime Drops and Rewards

Possible drops from King Slime include: Random Tier 1 Equipment, Slime Buckler, Gelat Ring.

Quest Board rewards for completing the King Slime event: Ferrus Skin, Potion, Small Health Potion, Essence, Gold.

Yar’thul, the Blazing Dragon

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Yar’thul is a fire-type boss, employing fire and inferno-based attacks. Most attacks inflict Inferno and Burning, making this a challenging fight without proper preparation. It resists fire and physical damage but is weak to Hex damage.

Yar’thul Location

Yar’thul resides deep within Mount Thul, an active volcano in the desert. Navigate the volcano's interior to find the Blazing Dragon.

Yar’thul Fighting Strategy

Yar’thul has 1200 HP (1800 HP if Corrupted). Its high damage output makes this a race against time. Below 50% health, it enters a second phase, summoning meteors that inflict stuns and healing reduction. The Dragon Ring and Pristine-level accessories are highly recommended. The Corrupted version gains lifesteal.

Attacks	Energy Cost	Effect
Inferno	0	Automatic attack inflicting Inferno. Cannot be dodged or blocked.
Fire Claw	0	Light damage fire claw attack.
Magma Pillar	2	Creates a magma pillar inflicting Inferno and Burning. Lasts 3 turns.
Blaze Core	3	Consumes Inferno stacks to heal.
Blaze Eruption	2	Damages burning targets, applying Inferno and Burning stacks.
Magma Beam	4	Massive damage beam attack. Cannot be dodged or blocked.
Hellfire	1	AOE fire attack applying Burning stacks. Cannot be dodged or blocked.
Armageddon	6	Below 50% health, summons a meteor inflicting massive damage, stun, and healing reduction. Cannot be dodged or blocked.

Yar’thul Drops and Rewards

Guaranteed rewards: Absolute radiance, Permafrost Curse, Wild Impulse, Heavenly Prayer, Breath of Fungyir, Narhana’s Sigil, Reality Watch, Shifting Hourglass, Ring of the Dragon, The Void Key (Corrupted Yar’thul).

Possible drops: Dragontooth Blade, Dragonbone Gauntlets, Dragonbone Spear, Dragonflame Shield, Memory Fragment, Soul Dust, Phoenix Tear, Resplendant Essence, Lineage Shard, Skyward Totem.

Thorian, the Rotten

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Thorian, once an animal, is now a corrupted monstrosity. It curses anything it touches and resists most elements, but is heavily weak to Holy damage.

Thorian Location

Thorian is found deep within the Cess Grounds in the Deeproot Canopy. Head right upon entering the Cess Grounds.

Thorian Fighting Strategy

Thorian has 2600 HP (3900 HP if Corrupted). A key mechanic involves its passive negation: attacking twice with the same attack type heals it. Vary your attack types. It resists most damage, except for Holy (135% damage). Below 50% health, it unleashes a devastating attack inflicting Plague, Curse, and Hexed (15-turn cooldown).

Attacks	Energy Cost	Effect
Cursed Wave	2	Damages 3 party members, chance to inflict Curse.
Overflowing Curse	0	Minigame; failure inflicts Plague. Cannot be dodged or blocked.
Cess Breath	1	AOE damage and debuffs.
Warped Crush	1	Damages 3 party members.
Blasphemous Obliteration	5	Below 50% health, inflicts Plague, Curse, and Hexed. Cannot be dodged or blocked.
Hexed Burst	1	AOE damage, chance to apply debuffs.
Plague Rupture	2	Applies a random debuff, then massive damage based on debuff count.

Thorian Drops and Rewards

Guaranteed rewards: Absolute Radiance, Permafrost Curse, Wild Impulse, heavenly Prayer, Breath of Fungyir, Stellian Core, Metrom’s Amulet, Darksigil, Ring of Blight, The Void Key (Corrupted Thorian).

Possible drops: Blightrock Dagger, Blightwood Staff, Memory Fragment, Soul Dust, Phoenix Tear, Resplendant Essence, Lineage Shard, Skyward totem.

Metrom’s Vessel

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Metrom’s Vessel is a raid boss, spawning on a global timer. A Void Key (obtained from defeating corrupted bosses) is required to participate. This boss is characterized by exceptionally high health and damage negation.

Metrom’s Vessel Location

Metrom’s Vessel's location is announced server-wide after it spawns.

Metrom’s Vessel Fighting Strategy

Metrom’s Vessel has 10,000 HP (15,000 HP if Corrupted). This fight is a long battle of attrition. It has two phases with different mechanics. Phase 1 involves destroying its wings to reduce damage negation, but fewer wings increase its damage output. It also summons Shadeblades. Phase 2 changes wing mechanics (Offensive and Defensive modes) and introduces a Mini Shadebringer.

Phase 1 Attacks

Attacks	Energy Cost	Effect
Rendering Slash	0	Damages and applies Weakness stacks.
Deathbound	1	Applies Sundered stacks to 2 players.
Eclipse	1	Applies a self-buff.
Invoke Shadeblades	3	Summons two Shadeblades (200 HP each). Cannot be dodged or blocked.
Hexed Rend	3	AOE slash inflicting debuffs. Cannot be dodged or blocked.
Oblivion	5	Deals 50% of everyone’s HP and inflicts Curse. Cannot be dodged or blocked.