Drill arm

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Drill arm

Drill arm

A mechanical arm replacement for speeding up mining. It has a built-in snake drill, which allows the miner to rapidly find and exploit weak lines in the rock. It also has a general-purpose manipulator. It is somewhat ungainly, which slows down movement slightly.

Base Stats

Medical ItemsBody Parts
Tech Level
Market Value
425 Silver

Melee Combat

Melee Attack 1
13 dmg (Stab)
2 seconds cooldown
20% armor penetration
Melee Average DPS
Melee Average AP


Crafted At
Machining table
Required Research
Specialized limbs Techprint
Skill Required
Crafting 5
Work To Make
15,000 ticks (4.17 mins)
Resources to make
Steel 60 + Component 8
ImplantEmpireCommon, DrillArm

The drill arm is an artificial body part that provides both the functionality of a normal arm, while also increasing Mining Speed by 160%, Deep Drilling Speed by 70%, and inflicting a -8% Moving penalty.


Drill arms can be crafted at a Machining table once the Specialized limbs research project has been completed. They require Steel 60 Steel, Component 8 Components, 15,000 ticks (4.17 mins) of work and a Crafting skill of 5.

They can also be bought from Outlanders and Empire settlements, and are occasionally found installed on raiders.


Body part

Drill arms replace the user's organic arm. Note that unlike every other artificial arm in the game, this part does not attach to the shoulder but instead the arm itself. This means that certain body part destructions can prevent its attachment and that the drill arm cannot be used after an artificial arm has been attached to that side. It is unknown whether this is a bug. They are universal and can be installed on either the left or right. The drill arm has a part efficiency of 100%. This fully replaces the functionality of a normal arm but provides no enhancement - when coupled with the arm body part having a Manipulation importance of 50%, it results in an increase in manipulation of up to 50% when replacing a missing or totally inoperable hand or arm. Manipulation, in turn, affects a great many stats. For a full list of affected stats, see Manipulation.

Other effects

Each drill arm also provides +160% Mining Speed and a +70 Deep Drilling Speed. The effects of two installed arms stack. These bonuses apply as offsets to the base value of the stat, and are then multiplied by Global Work Speed, Skill factors and Capacity factors meaning the final increase from installing a drill arm can be significantly more than the nominal values. See those pages for details.

Each drill arm also inflicts a −8% Moving penalty. Moving, in turn, affects the following stats: Hunting Stealth, Melee Dodge Chance, Move Speed. This results in a directly proportional change to a pawn's move speed, and a improvement in melee dodge chance equivalent to an losing −1.44 levels of Melee skill per arm replaced.


A drill arm replaces the natural "Fist" attack of the replaced arm with a more powerful Stab attack.

  • Name Damage DPS AP Damage Type
    Heart Human Fist 8.2 4.1 12% Blunt
    Drill arm Drill arm 13 6.5 20% Stab
  • Installation

    Installing the part requires 2,500 ticks (41.67 secs) of work, ?x medicine of ?? quality or better, and a Medical skill of 4.

    Removing the part requires ? of work, ?x medicine of ?? quality or better, and a Medical skill of ?.

    If the operation fails, the part has a chance[What Chance?] to be destroyed.


    The drill arm can be installed on pawns if one needs a lot of mining or deep drilling done quickly. The effect is especially potent for pawns with traits that modify global work speed, as the +160% / +70% bonus is added before multiplicative modifiers.

    Example: a healthy pawn with a mining skill of 8 (x100%), a single drill arm (+160% for mining / +70% for deep drilling), a combination of very neurotic and industrious traits (x(40+35)%) in a lit environment will have: (100% + 160%) x 100% x 175% = 455% mining speed or 170% x 100% x 175% = 298% deep drilling speed. This already greatly speeds up work, while a second drill arm will result in 755% mining / 420% drilling speed, which is likely an overkill unless one needs a lot of resources mined quickly.

    The field hand, a plant work - oriented counterpart, has the same behaviour in terms of bonus speed calculation.

    The moving penalty predominately slows move speed but also decreases melee dodge chance and hunting stealth. Note that move speed calculation applies penalties from armor before the scaling to moving capacity - so while an otherwise unencumbered dual-field handed pawn will be 0.74c/s slower than a regular unencumbered pawn, the field handed pawn in cataphract armor will only be 0.61c/s slower than an cataphract-suited unmodified pawn. That is, the qualitative 16% reduction in move speed is maintained, so the larger the move speed penalty, the closer modified and unmodified pawns become quantitatively.

    Version history

    • Royalty DLC Release - Added.
    • 1.1.2565 - part efficiency 50% -> 100%, boost 180% -> 160%, movement penalty,