Diablo 4's Season of the Construct introduces the Seneschal, a customizable robotic companion that fights alongside you in the battle against the forces of darkness. Unlike other companions in the game, the Seneschal's strength isn't tied to your character's gear alone-it relies on strategic upgrades using Governing Stones and Tuning Stones. To turn this mechanical ally into a formidable asset, you need a clear plan to unlock, customize, and power up its abilities. This guide breaks down every step to Diablo 4 Items upgrade your Seneschal effectively, from acquiring the necessary resources to optimizing its build for your playstyle.

Step 1: Unlock the Seneschal First

Before you can start upgrading, you must unlock the Seneschal. This companion becomes available early in the Season of the Construct questline, specifically during "The Ennead"-the third quest of the season. Zoltun Kulle will task you with retrieving the Seneschal construct, and completing this quest grants you your first Seneschal, along with basic instructions to customize it.

Don't skip any steps in the seasonal questline. Not only does it unlock the Seneschal, but it also rewards you with early Governing Stones and Tuning Stones-essential for your initial upgrades. Finishing the questline also unlocks free upgrades that lay the foundation for your Seneschal's power.

Step 2: Understand the Core Upgrade System: Governing and Tuning Stones

The Seneschal's upgrades revolve around two types of stones: Governing Stones and Tuning Stones. These stones determine your companion's abilities, playstyle, and overall effectiveness in combat. Mastering how they work is key to maximizing your Seneschal's potential.

Governing Stones are the foundation of your Seneschal's skills. You can equip up to 2 Governing Stones at once, each granting a unique ability-from healing beams and protective shields to AoE damage and status effects. There are 12 Governing Stones in total, each with different rarities and combat roles.

Tuning Stones augment the abilities of your equipped Governing Stones. You can equip 3 Tuning Stones per Governing Stone (for a total of 6), adding buffs like increased damage, longer ability duration, or additional effects. Some rare Tuning Stones, like Evernight and Genesis, offer powerful unique bonuses that can drastically change your Seneschal's performance.

Step 3: Farm the Essential Resources

To upgrade your Seneschal, you need to collect three key resources: Governing Stones, Tuning Stones, and Shattered Stones. Each resource serves a distinct purpose, and efficient farming is crucial to progress quickly.

Vaults are the best place to farm these resources. Completing a Vault guarantees one random Tuning Stone, and you'll encounter construct enemies that drop Shattered Stones-raw materials used to craft more stones at the Jeweler. Ward Woven Chests, found at the end of Vaults, also reward additional Governing and Tuning Stones.

Arcane Tremors are another valuable source. These events require you to close Voltaic Obelisks and summon the Herald of Malphas, which drops either a Governing or Tuning Stone when defeated. Arcane Tremors also yield plenty of Shattered Stones, making them a great complement to Vault farming.

Shattered Stones can be crafted into Uncertain Seneschal Stone Caches at the Jeweler, using 220 Shattered Stones and 24 Iron Chunks. Each cache contains a random Governing or Tuning Stone, perfect for filling gaps in your collection or getting duplicates to level up existing stones. Iron Chunks are easily obtained by breaking down unwanted gear at the Blacksmith.

Step 4: Level Up Your Stones to Maximize Potency

Both Governing and Tuning Stones can be leveled up to Rank 10, increasing their potency, damage, and effect duration. Leveling stones is simple: collect or craft duplicates of the same stone and fuse them together to grant experience.

Prioritize leveling stones that align with your playstyle. For example, if you use a healing-focused Seneschal, level up the Firefly Governing Stone (which heals you over time) and Tuning Stones that extend its duration or increase its healing output. Leveling stones to Rank 10 is essential for endgame content, as it significantly boosts your Seneschal's utility and damage.

Don't discard duplicate stones-even common ones. Fusing duplicates is the only way to level up your stones, so keep a stockpile of extras. If you craft a stone you already own, it automatically becomes a duplicate for leveling, making crafting a reliable way to D4 materials for sale progress.