Phlogiston Construct Creature (CR +0)

The so-called "natural philosophies" like alchemy and clockwork lag behind their flashier arcane counterparts; the phlogiston construct combines them. A phlogiston construct substitutes gears and steam for magic as its motive force. These creations demand more care in their construction and maintenance, but offer reliability even in the face of any magic. Phlogiston Constructs resemble their arcane counterparts, though most bear clockwork machinations like boilers, smoke stacks, or cooling towers.

Creating a Phlogiston Construct

"Phlogiston Construct" is a constructed template that can be added to any creature of the Construct type. A Phlogiston Construct creature uses all the base creature's statistics and special abilities except as noted here.

CR: +0

Size and Type: A Phlogiston Construct loses all subtypes.

Hit Dice: In addition to the bonus hit points normally gained for size, a phlogiston construct gains additional hit points based on the quality of its phlogiston core (see sidebar).

Special Attacks: Any of the constructs existing spell-like or supernatural abilities instead become extraordinary abilities.

Special Abilities: All of the constructs existing spell-like and supernatural abilities become extraordinary abilities.

Absorb Magic (Ex): A phlogiston core draws in energy to fuel itself, making the creation immune to all spells or spell-like abilities that allow spell resistance. This ability replaces any existing immunity, and the construct cannot lower this resistance.

Accessories (Ex): A phlogiston construct possesses one accessory for every three hit dice. Unless stated otherwise, the same accessory may not be selected twice.

  • Arcane Cell: Modifications to the core housing enhance the construct's normal immunity. As a swift action, the phlogiston construct may activate an antimagic field with a caster level equal to its hit dice. This field persists for one minute, and may be activated once per day. This accessory may be selected multiple times, adding an additional use per day.
  • Cannon: A mounted cannon fires one type of energy (chosen from the table below when the accessory is first installed) as a ranged touch attack, and requires 1d4 rounds to recharge afterwards before firing again. A cannon blast inflicts 1d6 damage per hit die.
Projectile Damage Type Range
Arc Coil electricity 30ft
Concusser sonic 10ft
Flame Projector fire 50ft
Steam Cannon slashing 100ft
Slug Launcher piercing 100ft
  • Clamp: An oversized pincer replaces one limb (and accompanying natural weapon), granting the construct a claw attack with the grab special ability.
  • Energy Channeling: Carefully engineered conduits funnel energies into the construct's core. The construct gains electricity and fire resistance 5. This accessory may be selected multiple times, increasing the resistances by 5 each time.
  • Enhanced Hydraulics: +2 Str.
  • Enhanced Gearing: +2 Dex.
  • Enhanced Turing Engine: +2 Wis.
  • Gas Vents: As a swift action, the construct can release steam and smog to cloud the area, as per an obscuring mist spell centered on the construct.
  • Industrial Plating: Heavy plates bolt on over the most vulnerable equipment and joints. The construct gains light fortification. This accessory may be selected multiple times, increasing the fortification by one category each time.
  • Integrated Weapon: A devastating melee weapon integrates into the construct's body, replacing one natural attack. Any light or one-handed simple or martial weapon may be selected, and the construct gains proficiency in its use. The integrated weapon is always masterwork, and may be enchanted separately. An integrated weapon is always treated as a primary attack and cannot be disarmed.
  • Pilot Compartment: A seat and housing built into the chassis comfortably seats a rider of up to one size category smaller than the construct. The pilot compartment provides partial cover and allows a rider control of the construct as a mount, substituting Knowledge (engineering) for Ride checks. Constructs with an Int higher than 2 may not be controlled, but still provide partial cover to their pilot. The compartment provides no protection from the construct's immense heat ability. This accessory may be selected twice, providing cover rather than partial cover.
  • Reactive Mechanism: A dazzling series of cogs allow the construct to react to specific combat situations. The construct gains one combat feat.

Delicate Systems (Ex): A phlogiston construct's mechanisms are more prone to damage than a magical construct's solid mass. The creature is susceptible to nonmagical ability damage and drain, fatigue, exhaustion, paralysis, and stunning effects. The construct cannot recover from these afflictions naturally, and requires a separate one-hour Knowledge (Engineering) check to remove each condition (DC equals 15 plus the construct's hit dice). Phlogiston constructs use steam for their motive force, and are susceptible to dehydration and suffocation. For these purposes alone, assume the construct's Con is 10 and treat the nonlethal damage as normal damage. Damage and fatigue from dehydration are removed immediately once a construct's tanks are refilled. Reactivating a suffocated construct requires a DC 20 Knowledge (engineering) check.

Immense Heat (Ex): The frenzy of movement in a fight overwhelms the construct's cooling systems. The phlogiston construct creature’s melee attacks deal an additional 1d6 fire damage. Creatures grappling with or attacking the construct with natural weapons also suffer this damage.

A phlogiston construct requires neither magic nor the Craft Construct feat to build. A dedicated engineer instead treats their ranks in Knowledge (engineering) as their caster level, and may ignore any spellcasting requirements. To begin the project, the engineer must succeed at a Knowledge (engineering) check (DC 15 + construct's hit dice), requiring two hours' work per hit die of the construct. Once completed, a phlogiston construct remains inactive until a phlogiston core is installed. The core must be constructed separately.

Phlogiston Cores

Phlogiston is the potential energy of fire found in burnable objects. The volatile substance's power can be stored and slowly released to whatever ends a roaring fire might be applied. Most commonly, tinkerers use reinforced phlogiston cores to power steam engines, freeing their devices from bulky boilers. While a core is nonmagical, many of its components can only be forged magically. The quality of a phlogiston construct's core directly affects its dependability, reflected as additional hit points per hit die. Phlogiston cores cannot be purchased, and must instead by crafted.
Core Bonus HP Craft DC Cost Lifespan
Core - 30 100gp/HD 1 year
Battery 1/HD 35 200gp/HD 2 years
Cell 2/HD 40 400gp/HD 5 years
Cortex 4/HD 45 800gp/HD 15 years

Constructing a phlogiston core requires the following spells: lightning bolt, heat metal, stone shape. The engineer does not need to cast these spells, but they must be cast during each skill check. For every spell unavailable, increase the Craft DC by +5. Removing a Phlogiston Construct's core immediately renders it inanimate. Doing so requires one minute of work and a DC 30 Knowledge (engineering) check.

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