Etherian Mana

Etherian Mana is used to summon Towers and Traps in the Old One's Army event. It has a high chance to be dropped by all of the Old One's Army event enemies. Each wave will produce Etherian Mana in multiples of ten - after receiving a starting amount of ten when activating the Eternia Crystal, each wave will produce either 20 or 30 Etherian Mana. Each Tavernkeep's sentry costs 10 Etherian Mana/Use, so conserving Etherian Mana and developing a strategy is key to the event. This item will disappear after the invasion has ended, along with all event enemies.

Trivia

 * Prior to 1.4.0.1, it is possible to keep the Etherian Mana by placing it in a chest (do not open it again if the event isn't in progress or it'll be lost) before the Old One's Army event ends. (Tested in 1.4.0.4, it is still possible to do this in a regular chest, but only in multiplayer)
 * However, it is still possible to contain Etherian Mana inside a Money Trough as long as it is not opened if the event isn't active.
 * In the game code, prior to 1.3.5, its name was "its an ammo technically!". Because the actual name was stored in a separate file, this wouldn't display.
 * Etherian Mana is one of the only items that cannot be researched in . As such, it cannot be duplicated, the "research [number] more to unlock duplication" tooltip is not displayed, and the researching UI will show an X when it's put in the slot.

History
Mana d'Etheria 天国魔力