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▾Table of Contents▾
Mutagen item
Mutagen is an unlockable passive item in Arachna, a mod for The Binding of Isaac.
Description
+1 damage.
20% chance to spawn 3-5 special friendly spiders when entering a new room.
All spiders spawned outside of Spider Eggs have a chance to be special.
How to unlock?
Defeat Delirium as 
Arachna.
Item pools
Mutagen can be found in the following item pools:
| Name | Weight |
|---|---|
| Treasure Room |
1.0/1.0
|
| Red Chest |
1.0/1.0
|
| Curse Room |
1.0/1.0
|
| Greed Treasure Room |
1.0/1.0
|
| Greed Curse Room |
1.0/1.0
|
Tags
The following tags are applied to this item:
| Id | Description |
|---|---|
| offensive | Can appear for  Tainted Lost. |
| summonable | Can be summoned via  Lemegeton. |
External links
- Check out the item description on the mod's external Wiki.
- Download Arachna from the Steam Workshop.
Arachna's Spool 
Divine Cloth 
Yarn Heart 
Lil Arachna 
Best Bud Ball 
The Yarn