Talk:Spectre Armor/@comment-4511886-20131017133237/@comment-24013733-20131017152000

That's the, ah, what's it called... Wisp in a Bottle? Is that it? (If it is, the link will work, haha). Rare drop from some Hardmode Dungeon critters, as I recall. It's kind of like the Fairy Bell and the Shadow Orb spells, except it mimics your movement and never falls behind like those two do.