A hell engine is a construct fueled by an infernal contract, bypassing the complex magic and craftsmanship needed to animate a golem or similar engine of destruction. Artificers who lack the skill or magical aptitude to craft constructs on their own may be tempted to use the power of Hell to make up for their shortcomings, surrendering their souls for the chance to see their masterpieces brought to horrifying life.
Although a hell engine lacks the creativity and cunning of a true devil, contracting an infernal construct grants certain advantages over a bound outsider. A hell engine’s mindless neutrality renders it resistant to anarchic or holy attacks that would cripple a devil, making it a valuable tool against celestial and chaotic forces. Combined with the construct’s ability to banish hostile outsiders and replace them with additional devils, these war machines earn a distinguished place as shock troops in infernal armies and guardians of Hell’s most secure vaults.
The sample hell engine above uses an adamantine golem as the base creature.
Creating a Hell Engine
“Hell engine” is an acquired template that can be added to any nonchaotic, nongood construct with no Intelligence score. A hell engine uses all the base creature’s statistics and special abilities except as noted here.
Challenge Rating: Base creature’s CR + 1.
Alignment: Always neutral. However, a hell engine radiates a moderate aura of law and evil as if it were a lawful evil outsider.
Senses: A hell engine gains the see in darkness ability. In addition, the hell engine can see through the hellfire cloud created by its breath weapon without penalty, ignoring any cover or concealment bonuses it provides.
Defensive Abilities: A hell engine gains fire resistance 30. If the base creature has immunity to magic, it gains the following change: • Dispel evil or dispel law drives the hell engine back 30 feet and deals 2d12 points of damage to it (no save).
Weaknesses: A hell engine gains the following weakness.
Contract Powered (Ex)
A hell engine draws power from the infernal contract that animates it. A hell engine cannot attack the devil that drafted its contract, the mortal who signed it, or any creature holding an original copy of the contract. Spells cast by the devil that wrote the contract or its mortal signatory automatically bypass any spell resistance or immunity to magic the hell engine has. If both copies of the contract are destroyed, the hell engine ceases to function until a new one is created.
Special Attacks: A hell engine gains the following.
Breath Weapon (Su)
As a standard action once every 1d4+1 rounds, a hell engine can exhale a churning cloud of hellfire in an adjacent space equal to its own size. This hellfire persists for 1 round; each creature within the area when the hell engine creates it (as well as any creature that passes through the cloud until the start of the hell engine’s next turn) takes 1d6 points of fire damage and 1d6 points of unholy damage per 2 Hit Dice of the base creature. A creature can attempt a Reflex save (DC 10 + half the base creature’s HD) for half damage. The hellfire cloud also provides concealment as if from a fog cloud spell.
The hell engine can use this breath weapon in addition to any breath weapon the base creature has, and it can use up to two breath weapons simultaneously as a full-round action. Simultaneous breath weapons both fill the area of either the hellfire breath weapon or base creature’s breath weapon (hell engine’s choice). If the base creature’s breath weapon deals fire damage, a simultaneous breath weapon converts half of that damage into unholy damage.
Banishing Strike (Su)
Three times per day as an immediate action, the hell engine can force an extraplanar or summoned creature it hits to attempt a Will save (DC = 10 + half the base creature’s HD); on a failure, the target is forced back to its original plane as if by a dismissal spell.
Redirect Summons (Sp)
Within 1 minute of successfully using its banishing strike ability, a hell engine can redirect its planar energy to summon a devil as an immediate action with a 100% chance of success. The summoned devil remains for 1 hour. A hell engine can have only one summoned devil at a time. The hell engine’s Hit Dice determines the most powerful kind of devil it can summon and the effective spell level of this ability, according to the following table.
While a typical golem uses an elemental spirit as its power source, a hell engine draws power from a special infernal contract. A hell engine requires the same physical body as its base creature, but the creator need only sign a contract and surrender his immortal soul to animate the construct. Typically a devil drafts a contract that grants the mortal signee some service performed by the hell engine, with mastery of the construct transferring to the devil upon completion of the task or the mortal’s demise.
As with all infernal contracts, animating a hell engine is always a lawful and evil act.
The hell engine generally serves as an intermediary in the contract’s stipulations, allowing clever mortals or devils to exploit loopholes in the agreement via the construct itself. For example, destroying a hell engine before it completes its contractual task or the mortal signee dies may nullify the contract, releasing the soul from damnation. Most devils include clauses to prevent a signee from destroying its own construct. A hell engine that becomes inactive due to a breach of contract, exploitation of a termination clause, or destruction of the original contracts can be reused to generate a new hell engine or to create a normal version of the base creature.
Powerful hell engines require more soul energy to activate; the devil and the mortal signing the contract must each have at least 1 Hit Die per 2 Hit Dice of the hell engine they wish to animate. A devil can use multiple souls to fuel the same hell engine as long as the total number of Hit Dice between the mortal signatories equals at least half the Hit Dice of the construct. However, convincing numerous mortals to sign away their souls for shared custody of a construct can be difficult, even for an accomplished dealmaker.
Pathfinder Campaign Setting: Construct Handbook © 2018, Paizo Inc.; Authors: Brian Duckwitz, Andrew Hoskins, Nathan King, Kris Leonard, Luis Loza, Adrian Ng, Tom Phillips, Alex Riggs, and Nicholas Wasko.