Starfinder: Plasma Arachnid

Chris Van Deelen

Plasma Arachnid Combatant CR 20 XP 307,200

Neutral Gargantuan Vermin

Init +0; Senses: Darkvision 60 ft.; Perception +34


Defense                                                             HP 500

EAC: 35; KAC: 37

Fort: +23 (+33); Ref: +21; Will: +17

Defensive Abilities: Damage reduction 20 / -, energy resistance 20, hardened survivor; Immunities: Poison, radiation

Weakness:  Piercing and explosion vulnerability



Speed: 10 feet.

Melee: Two stomps +30 (6d12+40 B Crit knockdown)

Ranged: Plasma blast +31 (5d12+20 E&F)

Space: 40 ft., Reach: 20 ft.

Offensive Abilities: Plasma blast



Str +20; Dex +0; Con +7; Int -; Wis +0; Cha +0

Skills:  Intimidate +39, survival +34

Languages: None



Environment: Any

Organization: solitary, small groups (1d3+1) or small artillery platoons (2d6+1)


Special Abilities

Hardened Survivor (Ex): The Plasma is completely immune to poisons and radiation, and it is able to withstand extreme conditions, even utter vacuum. Whenever the beast must make a saving Fortitude saving throw when dealing with environmental conditions, it gains a +10.

Piercing and explosion vulnerability (Ex): Due to the massive buildup of explosive energy contained inside this arachnid, any single piercing or explosive attack which inflicts 50 points or more in a single attack will force the creature to make a Fort Save DC 35 or immediately explode. This explosion has a radius of 350 feet and anything inside the radius (including other Plasma Arachnids) must likewise make a Reflex save (DC 35) or be killed outright. This will cause other Plasma Arachnids to possibly explode as well, causing a chain reaction! Even if those inside the area of effect make the save, they will still take 20d6+20 points of F & E damage.

Plasma Blast (Ex): Once every 5 rounds the Plasma Arachnid is able to generate a sufficient charge of plasma energy and launch it into space. This causes 5d12 damage to starships and has a long range. It can also fire this blast off at any ground targets within 3000 feet, but never close enough that it would endanger itself. Anything caught in the blast radius (see piercing and explosion vulnerability) are subject to the same save and damage.


Probably the largest of the Arachnids, the Plasma is the artillery of the species. These huge beetle-like creatures have a massive armored abdomen, which generates plasma at prodigious rates. The plasma is then fired off every five rounds, launching a massive ball of energy into the atmosphere in order to attack enemy starships – or it can be used as artillery to strike ground targets.

As stated, the abdomen is huge with a capital H!  While the body is significantly smaller. It moves around on 8 segmented legs, which it can use to stomp on anyone foolish enough to get within range, otherwise it relies on other Arachnids to protect it.  The beast is easily 40 feet in length and weighs in excess of 40 tons. It has two large blue eyes, which are able to see even the smallest detail, and they can easily see through the atmosphere into space in order to locate enemy starships to attack.

Typically these creatures are found in groups, which are spread out over a large area, to prevent possible catastrophic damage if any of the creatures are targeted and destroyed. They are always under the control of a Thinker Arachnid, but are still capable of picking and firing at targets if the link to the thinker is somehow severed.

Starfinder Creature Index

Chris Van Deelen is the creator and contributor to over half of the Wisdom from the Wastelands series, contributor to the Swords of Kos: Hekaton anthology. He also wrote Creatures of the Tropical Wastelands, and 100 Oddities found in a Car. As prolific as he is, Chris Van Deelen continues to write and produce material which will be in publication soon. Not only is he a prolific content creator, he also has a wide selection of fiction and stories! If you like his work, please follow his personal author page on Facebook and on Twitter to keep up with his latest news and game content.