In Oblivion (and Oblivion Remastered), ectoplasm mainly comes from killing ghost‑type enemies and from a handful of alchemy shops and dungeons.

Fast ways to get ectoplasm

  • Fight ghosts / wraiths: Ectoplasm is a common drop from ghosts, ancient ghosts, wraiths, faded wraiths, gloom wraiths, and similar spectral enemies.
  • Great Chapel undercrofts: The crypt areas under chapels (Anvil, Bruma, Bravil, Leyawiin, Skingrad) usually contain 3–5 spectral undead you can farm for ectoplasm, though many doors are locked and may need a key or lockpicking.
  • Rielle dungeon (near Bruma): A popular “quick farm” spot; heading northwest from Bruma to the Ayleid ruin Rielle lets you fight several ghosts and grab multiple guaranteed ectoplasm drops in one run.

Good quest and dungeon spots

These places are known for lots of ghost spawns, so you’ll often walk out with a pile of ectoplasm:

  • Benirus Manor, Anvil – Quest “Where Spirits Have Lease,” the haunted house is packed with ghosts.
  • Serpent’s Wake (Anvil docks) – Quest “The Ghost Ship of Anvil”; the ship is full of spectral sailors.
  • The Forlorn Watchman – At the wreck of the Emma May near the Mouth of the Panther, another ghost‑heavy quest.
  • Sancre Tor, Vahtacen, Rielle – All have guaranteed ethereal undead spawns and are widely recommended farming spots.

Buying ectoplasm (if you’d rather pay)

  • All Things Alchemical (Skingrad): Often cited as the key early‑game place to either buy ectoplasm or grab a static sample on a table.
  • Imperial City Market District: The Gilded Carafe and The Main Ingredient can sometimes stock ectoplasm, though it’s rare.
  • Other alchemy vendors / Mages Guild alchemists: Various alchemy shops across Cyrodiil have a low chance to sell ectoplasm in their ingredient lists.

Quick reminder on how to fight ghosts

Spectral enemies are immune to:

  • Normal (unenchanted) weapons
  • Frost damage
  • Poison
  • Silence effects

So make sure you bring enchanted or silver weapons, or use offensive spells to actually damage them and farm ectoplasm efficiently.

TL;DR: For “oblivion where to get ectoplasm,” hit chapel undercrofts or Rielle to farm ghosts, and check All Things Alchemical plus Imperial City alchemy shops if you prefer to buy instead.

Information gathered from public forums or data available on the internet and portrayed here.