Ben 10 Fan Fiction Wiki
Ben 10 Fan Fiction Wiki

Demonstar is a villain in the series 40: The Last Splixson, an Osmosian warlord with lethal absorbing powers. Father to Necropolix, Uncle to Azeroth and Inbenton. He is killed by his own sword after an intense battle with Fred in "Invasion of Galvan, Part 2: The Invasion".


Demonstar is a hulking chimerical behemoth fusion of countless alien species.

  • Pyronite: Torso and head.
  • Methanosian: Left arm
  • Tetramand: Arm count
  • Cerebrocrustacean: Right hand pincer
  • Biosovortian; Left shoulder spike
  • Piscciss Volann: Lure
  • Transylian: Conductors on his back
  • Lepidopterran: Wings
  • Necrofriggian: Right wing structure
  • Polymorph: Right arm structure
  • Crystalsapien: Right arm shoulder spikes
  • Arachnichimp: Lower right arm
  • Vulpimancer: Lower left arm structure
  • Merlinisapien: Lower left arm
  • Appoplexian: Left arm claw
  • Prypiatosian-B: Left shoulder
  • Geochelone Aerio: Torso
  • Arburian Pelarota: Right arm plate
  • Talpaedan: Right arm jackhammer
  • Florauna/Vaxasaurian: Tentacle structure

Powers and Abilities

  • Energy Absorption
  • (Absorbed Alien's Powers and Abilities)


40: The Last Splixson

He appears at the end as a dark, mysterious silhouette.

He hires a mercenary to lure Fred away from his team and capture him.

He tortures Fred with visions of the Splixson Massacre and and later battles him.

He tracks Fred down and invades Galvan Prime. He battles Fred and has his powers erased by Powerdrain. A weaker version of Demonstar attempts to strike back, but is sliced by his own sword. Boulder crushes his ribs resulting in his permanent end.