Here’s exactly how to make a fermented spider eye in Minecraft, plus some quick extra tips for potions and gameplay context.

Quick Scoop: Core Recipe

To craft a fermented spider eye in Minecraft, you need three items:

  • 1 Spider Eye
  • 1 Brown Mushroom
  • 1 Sugar

Then:

  1. Place a Crafting Table and open the 3×3 crafting grid.
  2. Put the spider eye , brown mushroom , and sugar anywhere in the grid (order and exact positions do not matter in current versions).
  3. Take the Fermented Spider Eye from the result slot into your inventory.

That’s it – one set of those three ingredients gives you one fermented spider eye.

Mini Section: How to Get Each Ingredient

To actually make a fermented spider eye, you’ll first need to gather the components:

  • Spider Eye
    • Dropped by spiders and cave spiders when killed.
    • Also sometimes found in chests in generated structures in some versions.
  • Brown Mushroom
    • Found in dark or shaded areas: forests, swamps, caves, and the Nether.
    • Also grows on giant mushrooms and can be generated in mushroom fields.
  • Sugar
    • Crafted from sugar cane.
    • Place 1 sugar cane in the crafting grid to get sugar.

Once you have all three, you’re ready to craft.

Mini Section: Step‑by‑Step Crafting Flow

Think of it as a tiny in‑game “alchemy” moment:

  1. Set up your station
    • Place a Crafting Table if you don’t already have one.
  1. Open the crafting menu
    • Use the Crafting Table to open the 3×3 grid.
  1. Add the ingredients
    • Put in:
      • 1 spider eye
      • 1 brown mushroom
      • 1 sugar
    • You can place them in any pattern in the 3×3 grid; Minecraft recognizes the combination, not the layout.
  1. Collect your fermented spider eye
    • Drag the fermented spider eye from the output slot into your inventory.

Example layout that works (3×3 grid):

  • Top row: Brown Mushroom – Sugar – (empty)
  • Middle row: Spider Eye – (empty) – (empty)
  • Bottom row: all empty

But again, any positions are fine as long as all three ingredients are present.

Mini Section: What It’s Used For (Potions)

Fermented spider eyes are mainly used in brewing to create certain “negative” or special-effect potions. You’ll need:

  • A Brewing Stand (crafted from 1 blaze rod + 3 stone blocks, or found in villages).
  • Water bottles and fuel (blaze powder).

Some common uses:

  • Turning certain potions into Potion of Weakness, Slowness, or Harming when used on the right base potions.
  • Creating or modifying Invisibility potions when combined with the appropriate base potion.

In other words, the fermented spider eye is a key “corrupting” ingredient that twists existing potions into more sinister or tactical ones.

Mini Section: Quick Tips & Notes

  • You don’t need any special workstation to craft the fermented spider eye itself beyond a normal Crafting Table.
  • Farm spiders at night or in mob farms to keep a steady supply of spider eyes.
  • Brown mushrooms can be farmed by placing them in low light and bonemealing them to grow giant mushrooms.
  • Keep extra sugar cane planted near water so you never run out of sugar.

In current Minecraft, once you remember “spider eye + brown mushroom + sugar = fermented spider eye,” you’re basically set for any potion‑brewing session.

TL;DR:
To make a fermented spider eye, combine 1 spider eye, 1 brown mushroom, and 1 sugar in a Crafting Table’s 3×3 grid in any arrangement, then use it for advanced potion brewing like weakness, harming, and invisibility.

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