Eternia Crystal

The Eternia Crystal is an event-summoning item. When used in the Eternia Crystal Stand, the Old One's Army event begins. The Eternia Crystal is purchased from the Tavernkeep for (pre-mechanical bosses),  (post-mechanical bosses), or  (post-Golem).

Tips

 * Players may wish to stock up on Eternia Crystals before defeating the mechanical bosses, in order to save coins.
 * Due to the price increase, it is possible to buy Eternia Crystals beforehand and sell them after the battles, netting a total profit of per crystal (This no longer works on desktop. The price you sell the crystal for is based on the price you bought the crystal for regardless of which bosses you have defeated).
 * This is not possible on the ; they sell for even post-Golem.