Creature Feature (Starfinder): Siegebreaker Robot

Siegebreaker Robot CR 18

This massive hulk of metal grinds forward, crushing barriers with its passage as its massive weapons lay waste to fortifications.

N Gargantuan construct (technological)
Init +8; Senses darkvision 100 ft., low-light vision, blindsense (movement) 40 ft.; Perception +31


EAC 32; KAC 34
Fort +19; Ref +19; Will +16
Defensive Abilities fortify, mindless, unliving


Speed 40 ft.
Melee kinetic cannon +32 (8d10+18 Bl & Fo, 100 ft. range)
Multiattack 4 point defense turrets +29 (5d8+22 P, 40 ft. range)
Ranged thermal drill +32 (13d6+29 Sl & F, critical burn)
Space 20 ft.; Reach 20 ft.
Offensive Abilities artillery cannons, doorbreaker, siege monster


Str +11; Dex +8; Con -; Int -; Wis +6; Cha +0
Skills Athletics +36, Engineering +31, Physical Science +31
Languages Common, two languages spoken by its creator or commander
Other Abilities controlled


Artillery Cannons (Ex)

A siegebreaker contains a small battery of artillery cannons it can use to bombard targets from a distance. As a standard action a siegebreaker targets and fires upon up to three 20 foot radius spheres, each of which must be within ten feet of another and cannot overlap. Everything within these spheres must make a DC 23 Reflex save or take 5d6 damage that is half Slashing and half Fire. These targeted areas may be anywhere at least 100 feet away from the siegebreaker itself up to a maximum range of 1000 feet. A siegebreaker does not need direct line of sight at the targeted areas, but any obstructions above the intended target will cause the artillery shells to detonate prematurely in their arc.

Controlled (Ex)

Siegebreakers have a series of limited programs in place of a true AI, so they are often micromanaged by a commander. A siegebreaker robot has a cockpit set deep within its body that such a commander can command it from and can receive electronic communication broadcasts to give it new commands. Until commanded otherwise, a siegebreaker will always continue following its last given command until destroyed.

Doorbreaker (Ex)

A siegebreaker is capable of temporarily drawing power away from the majority of its systems to overclock its kinetic cannon. Once every 1d6 rounds a siegebreaker can take a full round action to attack a 500 foot long, 5-foot-wide line originating from itself. Everything in the area must make a DC 23 Fortitude. On a failure a creature or object takes 10d6 damage that is half force and half bludgeoning, and takes half damage on a successful save. If the beam ever strikes an object that wholly blocks it and is not destroyed by the damage it takes, the line stops at it and goes no further. If the object is destroyed, the line continues until it reaches the end of its range or is stopped by a later object.

Fortify (Ex)

A siegebreaker is capable of setting itself into the ground and readjusting its armor plates for greater defense, sacrificing mobility and most of its armaments for greater protection. By taking a move action a siegebreaker can change from assault mode to fortification mode. In fortification mode its movement speed becomes zero and it cannot use its thermal drill or kinetic cannon. Instead it gains DR 10/-, its KAC and EAC increase by 2, and it becomes capable of using its Bombardment ability. Changing back to assault mode is a full round action.

Siege Monster (Ex)

A siege robot’s attacks deal one and a half times as much damage to structures, vehicles, and immobile fixtures, ignoring all hardness for such objects. Structures, vehicles, and other fixtures comprised primarily of adamantine are immune to this ability.


Environment warzones
Organization single, ram (2-4)

Siegebreaker robots are titanic war machines designed to tear down fortifications and barriers, a task they accomplish with frightening ease. A standard siegebreaker is equipped with a potent arsenal of weapons, the most common of which is their kinetic cannon. A weapon capable of battering down defenses through sheer kinetic force, siegebreaker robots can draw power away from their movement systems and other weapons in order to overclock it to frightening proportions. This overclocked beam is capable of punching straight though many defenses, sometimes carving through buildings and out the other side. At close quarters, a siegebreaker carries a thermal drill to cut through obstacles to its passage and widen openings in structures to allow allied troops to pour in. At great distance, siegebreakers carry potent long ranged artillery weapons to barrage enemy targets from a distance. All of this is rounded off by a series of point defense cannons used to pick off nearby infantry and prevent saboteurs from closing the distance.

These weapons make a siegebreaker a powerful war machine, but those with experience fighting against or alongside them know they have vulnerabilities that can be exploited. Their greatest weakness is their limited intelligence. While they have numerous interconnected subprograms that allow them to efficiently fulfill their purpose, such as being able to analyze structures to determine how best to bring them down, they lack true initiative and intelligence. They require constant supervision from commanders in order to use them to their full potential, as they will otherwise attempt to follow their most recent command to the best of their ability. This flaw has led to common war stories about siegebreakers continuing to attack an already destroyed structure or wandering aimlessly in search of a battalion it was supposed to link up that had since moved.

Another flaw is their dyssynchronous weapon ranges. Their point defense turrets have a shorter range in comparison to their sensors, meaning they are often aware of threats that it cannot effectively combat. This is most obvious when combatting fortified siegebreakers. Without their kinetic cannon, enemies can sit in the sweet spot between the point defense gun’s maximum range and the in-built minimum range of the artillery cannons to whittle it down. Hit and run tactics are the best recourse in such situations, getting close enough to damage it, fleeing when it returns to assault mode, then returning to attack again when it settles back down into fortification mode. Commanders of siegebreakers counter this flaw by deploying them alongside other troops to protect them, often in the form of a second siegebreaker.

Siegebreakers are as widely varied as the arenas of war in which they are deployed, in both appearance and armament. Most siegebreakers appear as simple hulking machines, barely distinguishable from particularly large and imposing tanks, while others take the form of large spider-like machines or rolling armor-plated orbs. Their equipment is similarly variable, traded out to be more effective in certain situations. Here are a few examples of alternate siegebreakers.

  • Anti-Personnel: Siegebreakers may lose their artillery cannons in favor of greater ability to combat large groups of infantry. Such a siegebreaker loses its Artillery Cannons ability but can make two additional attacks during its multiattack
  • Aquatic/Aerial: Siegebreakers can be deployed in gas giants or aquatic locales. The siegebreaker gains either a 40 ft. fly speed or a 40 ft. swim speed, but decreases both its KAC and EAC by 4, as armor plating must be stripped away to make place for the propulsion systems. Such a siegebreaker remains capable of hovering in place when fortified, preventing them from sinking or falling when they attempt to use their artillery cannons.
  • Chemical Warfare: Siegebreakers can trade their normal artillery shells for ones carrying payloads of toxic gas. Such a siegebreaker’s artillery cannons instead force creatures to make a DC 23 Fortitude save. On a failure they take 5d6 damage and are blinded for 1d6+1 rounds, on a success they take half damage and are blinded for 1 round.
  • Fortcrusher: Some siegebreakers are used solely as mobile artillery platforms, discarding other weapons. Such a siegebreaker loses its kinetic cannon but can target six spheres with its artillery cannons ability.
  • Gatebreaker: Some siegebreakers rely on supporting troops for protection, replacing its point defense turrets with a second kinetic cannon. Such a siegebreaker loses its multiattack but can make two kinetic cannon attacks with its multi attack at +29 to hit and dealing 8d8+18 damage and can use its Doorbreaker ability once every 1d4 rounds.

About nwright

A freelance writer for the Open Gaming website who looks forward to building plots out of monster entries for you to enjoy as a player or DM.

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