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1. The Ultimate Lifeform who? by Kvitloken

   Fandoms: Sonic the Hedgehog - All Media Types, Alien: Isolation (Video Game), Alien (Original Movies 1979-1997)  

   • Mature
   • Graphic Depictions Of Violence
   • Gen, M/M
   • Work in Progress

   19 Apr 2025

   Tags

   • Graphic Depictions Of Violence
   • Shadow the Hedgehog/Sonic the Hedgehog
   • Miles "Tails" Prower & Sonic the Hedgehog
   • Rouge the Bat & Shadow the Hedgehog
   • E-123 Omega & Rouge the Bat & Shadow the Hedgehog
   • Amy Rose & Sonic the Hedgehog
   • Sonic the Hedgehog
   • Amy Rose (Sonic the Hedgehog)
   • Shadow the Hedgehog
   • Rouge the Bat
   • E-123 Omega (Sonic the Hedgehog)
   • Miles "Tails" Prower
   • Knuckles the Echidna
   • Xenomorph Characters (Alien Series)
   • Survival Horror
   • Slow Burn
   • Crossover
   • Horror
   • Space Stations
   • Outer Space
   • Shadow and Sonic haven't met yet
   • Maria Robotnik and Shadow the Hedgehog are Siblings
   • Rouge the Bat and Shadow the Hedgehog are Best Friends
   • Other Additional Tags to Be Added
   • My First Fanfic
   • no time for romance we gotta survive!
   • Shadow the Hedgehog is So Done
   • Shadow the Hedgehog aka Ellen Ripley
   • It's an au what do you want
   • Game: Sonic X Shadow Generations (2024)
   • Sonic x Shadow generations AU
   • Only the start really
   • More or less just merged isolation and generations
   • It's basically just isolation but with sonic characters instead
   • alpha read
   • Beta Read
   • Beta reader wants you t know it's called alpha reading
   • shadow the hedgehog is a badass
   • Minor Character Death
   • Badass Amy Rose (Sonic the Hedgehog)
   • Eventual Relationships
   • its jsut a side plot but obv i needed to bring sonadow into this somehow

   Summary

   Shadow didn’t ever think he’d return. After almost 50 years, he was finally coming back to the place haunting his every thought and dream. He had been all alone after Maria died, trapped inside his own consciousness. As the ultimate lifeform, he didn’t simply sleep during cryofreeze. He had been wide awake for 50 years, trapped inside his own mind and body until the doctor set him free. He had been so focused on getting revenge for Maria after that, he had completely forgotten her last wish, which resulted him almost eliminating the earth. Almost.

   Aka, Alien and Sonic crossover where Shadow, the ultimate lifeform, has to face the xenomorph, also the ultimate lifeform.

   Language:

   English

   Words:

   1,990

   Chapters:

   2/?

   Comments:

   6

   Kudos:

   9

   Bookmarks:

   5

   Hits:

   145