With the launch of Path of Exile 3.26 and the Mercenaries of Trarthus league, players were introduced to a variety of powerful new skill gems and support mechanics tied to the ancient mercenary culture of Trarthus. Among these, Sunder of Trarthus stands out as one of the most impactful melee skill variations we've seen in recent memory. In this article, we'll break down what Sunder of Trarthus is, how it differs from the traditional Sunder, the mechanics that govern its playstyle, its scaling potential, and which builds and Ascendancies best make use of it.

What Is Sunder of Trarthus?

Sunder of Trarthus is a unique variant of the classic Sunder skill gem. In the base version, Sunder is a melee slam skill that sends out shockwaves in a straight line, dealing area damage to enemies in its path. While effective, the traditional Sunder had fallen out of favor in recent metas due to its clunky mechanics and slower feel.

The Trarthus variant reimagines this classic skill with the Mercenaries league's design philosophy—faster, more impactful, and synergizing with the new Resonant Echoes and Fury Triggers mechanics.

Key Differences:

Shockwave Explosion Radius Increased: Trarthus Sunder sends out circular shockwaves instead of linear lines, making the AoE more consistent in packs.

Echoes with Fury Charges: Each shockwave generated while you have Fury Charges produces an Echo Slam, mimicking your attack with reduced damage but full area effect.

Built-in Knockback and Armor Penetration: A nod to the brutal combat style of the Trarthan mercenaries.

Synergizes with Mercenary Companions: Each shockwave has a chance to trigger Mercenary Shout, buffing your allies' attack speed and damage for a short duration.

How to Obtain Sunder of Trarthus

Sunder of Trarthus is not found through traditional gem vendors or the questline. Instead, it is acquired in one of the following ways:

League Mechanic Reward: Completing level 5+ Mercenary Contracts has a chance to reward a Trarthan Skill Gem Casket, which can contain this gem.

Vendor Recipe: Combine a regular Sunder gem with a Resonant Catalyst, Fury Shard, and an Ancient Trarthan Weapon Fragment.

Purchase from Rog (if unlocked via Mercenary Favor) once you've obtained it once in your account.

Due to its rarity early in the league, prices for Sunder of Trarthus can be quite high on the trade market. However, by mid-league, it becomes more accessible as more players begin farming the appropriate contracts.

Mechanics and Interactions

Understanding Sunder of Trarthus requires digging into a few key mechanics:

1. Echo Slams

Echo Slams deal 50% of base Sunder damage.

Can overlap with the main shockwave, creating “double-hit” scenarios.

Echoes scale with attack speed, not cast speed.

They count as secondary attacks, and thus benefit from “increased secondary damage” modifiers.

2. Fury Charges

Every Fury Charge active when using Sunder of Trarthus adds an Echo Slam.

Fury Charges grant:

+5% attack speed per charge

+5% physical damage per charge

Max number of Fury Charges is 3 by default, up to 6 with gear and passives.

3. Knockback and Armor Penetration

All hits from Sunder of Trarthus have a 100% chance to knock enemies back (can be modified).

Shockwaves penetrate 20% of enemy armor, increasing its effectiveness in high-armor endgame content.

4. Mercenary Shout Procs

10% chance per shockwave to trigger a Shout.

Shouts last 4 seconds, granting +15% attack speed and +20% damage to you and nearby allies.

Shares cooldown with other Warcries.

Best Builds for Sunder of Trarthus

1. Juggernaut Fury Slammer

Ascendancy: Juggernaut

Main Weapon: Two-Handed Mace (Kaom's Primacy, Tidebreaker)

Defensive Scaling: High armor, Fortify, Endurance Charges

Strengths:

Excellent survivability

Can stand in the middle of packs and slam freely

Synergizes with Fury and Endurance charges

Passive Tree Tips:

Prioritize area of effect, slam nodes, and charge generation

Use Unstoppable and Undeniable for scaling attack speed

2. Slayer Echo Chain Crit

Ascendancy: Slayer

Main Weapon: Crit-focused Two-Handed Sword or Axe (Starforge, Atziri's Disfavour)

Strengths:

Leech synergizes with multi-hit echo damage

Overleech + Echo slams = high sustain

Great for mapping and bossing alike

Recommended Supports:

Melee Physical Damage

Brutality

Echo Slam (new support)

Pulverise

Rage Support (to fuel Berserk)

3. Champion Warcry Commander

Ascendancy: Champion

Utility Scaling: Uses Shouts and minions from Mercenary Contracts

Strengths:

Buffs teammates, good in party play

High armor/evasion scaling

Combines utility with offense

Endgame Scaling and Gear Recommendations

Priority Stats

Attack Speed: More speed = more Echo Slams

Area of Effect: Increases both shockwave range and echo radius

Physical Damage: Always scale base physical; no elemental conversion

Fury Charge Duration: Extend uptime with gear/passives

Key Items

Kaom's Heart – Massive life pool for tanky slammer builds.

Callinellus Malleus – New unique two-hander that scales Echo Slam damage per charge.

Trarthan Girdle – Belt that grants +1 to maximum Fury Charges.

Amulet of the Mercenary King – Grants increased chance to trigger Shout and more shockwave area.

League Synergy: Mercenaries of Trarthus

The synergy between this gem and the league mechanic cannot be overstated:

Mercenary Contracts often include Fury Shrines that buff Echo generation.

Hiring specific mercenaries like Korath the Ravager gives on-hit Fury Charge gain.

Echo-based builds thrive in small room layouts common in these missions.

To maximize your farming and DPS potential, always bring contracts with shockwave-enhancing modifiers and use Fury Flask modifiers from the league system to keep charges up.

Mapping vs Bossing

Mapping: Sunder of Trarthus clears excellently with overlapping shockwaves. Echo slams obliterate dense packs and make breach encounters a breeze.

Bossing: Stack Fury Charges before engagement. Use Berserk, Warcries, and damage flasks to unleash maximum echo slam barrage. With the right timing, a single slam can deal massive burst damage thanks to overlapping hits.

Final Thoughts

Sunder of Trarthus brings a much-needed evolution to a once-popular melee skill, introducing a high-octane playstyle that Path of exile Items rewards positioning, charge management, and area control. Whether you're a veteran slammer or a new player looking to experience a brutal melee build, this gem offers a fresh take on physical AoE carnage in Path of Exile's 3.26 Mercenaries of Trarthus league.

As the meta continues to develop, expect more synergy between Echo-based skills, charge stacking, and support gems that reward active gameplay. Keep your Fury up and slam through the echoes of Trarthus.