Path of Exile · Passive node
Keystone passives
Keystones significantly alter character function, though the supplied passage does not describe individual Keystone effects.
How it works
The source distinguishes Keystones from small passives and notables by saying they significantly alter how the character functions. It also notes that some Keystones are granted exclusively from unique cluster jewels and unique Timeless Jewels. No specific Keystone effect or acquisition condition is supplied, so this record describes the category rather than recommending a particular Keystone.
Read the supporting references
Check the edition and source version for patch-specific details. Guide methodology.