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1. We Were Never Built to Last by forest_entity

   Fandoms: Iron Lung (2026), In Space With Markiplier (Web Series)  

   • Mature
   • Creator Chose Not To Use Archive Warnings
   • M/M
   • Work in Progress

   27 Mar 2026

   Tags

   • Creator Chose Not To Use Archive Warnings
   • Head Engineer Mark (In Space With Markiplier) & Simon (Iron Lung)
   • The Convict | Simon (Iron Lung)/Head Engineer Mark (In Space With Markiplier)
   • Head Engineer Mark (In Space with Markiplier)
   • The Convict | Simon (Iron Lung)
   • Ava (Iron Lung)
   • the ensemble cast
   • Canon-Typical Violence
   • Alternate Universe - Canon Divergence
   • Hurt/Comfort
   • Trauma Bonding
   • Hallucinations
   • Angst
   • Lore - Freeform
   • i made the c.o.i. more evil than they are in the movie
   • Religious Imagery & Symbolism
   • Guilt
   • They both need a Hug
   • Alcohol
   • Mark is the one who talks to Simon through the radio
   • Slow Burn
   • Whump
   • Eldritch Horror
   • Other Additional Tags to Be Added
   • this is gonna be a long one so strap in
   • Fix-It
   • except it gets worse before it gets better

   Summary

   The warp core is missing, and so are the stars. Stuck in a dead universe no way back to his crew, Mark is forcefully taken in by the C.O.I and tasked with building the SM-13. It's the strongest ship they've got, but something isn't right. People are still dying, despite the sub remaining untouched. Determined to help and rebel against their tactics, Mark concocts a plan to stay in communication with the next convict they send down, without the C.O.I's knowledge.

   Simon can't make sense of it, this C.O.I member wanting to help him, his strange ramblings of other universes and wormholes and paradoxes. The company was nice, he supposed. As the two exchange theories and conversations and comforts, the horrors persist, secrets are unearthed and discoveries are made that could possibly change everything.

   But why does it feel like they're the only ones who care?

   Language:

   English

   Words:

   39,931

   Chapters:

   6/?

   Comments:

   180

   Kudos:

   261

   Bookmarks:

   75

   Hits:

   3,294