Phantasmal Armor

Chest equipment — Legendary

Your Spectral Acorns instead have, " : Gain +, gain three of the same threshold of your choice, and return this to your hand. Then, this irreversibly transforms into a Mystic Squirrel."

Changes: Spectral Acorn
Slot: Chest
Rarity: Legendary
Set: Kickstarter
How obtained: Kickstarter

What it does is the game's own text; how it was obtained is from the owner's records.