Essence of Horror

One of four essences used to craft Crystal Disk of Dreams for unlocking the Suppressed Power on:

The Mindsunder loot

 * Death's Touch - ,
 * - Lesser Vampirism
 * Elocator's Habiliment - Greater Nimbleness
 * Gloves of Titan's Grip -, , Repair Systems
 * Light and Darkness - ,
 * Quorforged Docent of Battle -, Toughness
 * Rahl's Might
 * Axiomatic version -
 * Bleed version -
 * Force version -
 * Impact version -
 * Shock version -
 * Regalia of the Phoenix - ,
 * Terror - ,

The Reaver's Fate loot

 * Dreamspitter -

Unique Items with Non-Unique Locations
"Any newly generated Ioun Stones will have suppressed power." - developer Eladrin

"The intention was to make the Ioun Stones 'Bound to Account on Upgrade, but Binds to a Character on Equip', but that didn't work so well and I apparently mashed random buttons in the minimum level column. (...) Let's put them into the 'may be subject to change, but no rush' bucket." - developer Eladrin
 * This item.. - ...becomes this item when unsuppressed
 * Dark Blue Ioun Stone (unsuppressed) -, (ML: 5 BtC)
 * Deep Red Ioun Stone (unsuppressed) - Dexterity Skills - Exceptional Bonus +1 (ML: 5, BtC)
 * Dusty Rose Ioun Stone (unsuppressed) - (ML5, BtC)
 * Incandescent Blue Ioun Stone (unsuppressed) -, Wisdom Skills - Exceptional Bonus +1 (ML: 5, BtC)
 * Pale Blue Ioun Stone (unsuppressed) -, Strength Skills - Exceptional Bonus +1 (ML: 5, BtC)
 * Pale Lavender Ioun Stone (unsuppressed) - (ML: 5, BtC)
 * Pink Ioun Stone (unsuppressed) -, Constitution Skills - Exceptional Bonus +1 (ML: 5, BtC)
 * Pink and Green Ioun Stone (unsuppressed) -, Charisma Skills - Exceptional Bonus +1 (ML: 5, BtC)
 * Scarlet and Blue Ioun Stone (unsuppressed) -, Intelligence Skills - Exceptional Bonus +1 (ML: 5, BtC)
 * Vibrant Purple Ioun Stone (unsuppressed) -, (ML: 5, BtC)

Can drop from the end chest of Eye of the Titan