Ancients Awakened/Soul Stone

The Soul Stone was a Post-Moon Lord accessory that granted 6 extra minion slots along with the Hunter, Dangersense, and Spelunker buffs. It was obtained by throwing a Goblin Tinkerer Doll into lava. You were limited to 1 soul stone per player. The Soul stone was immensely useful for summoners due to it’s high minion cap boost, as well as being great for exploration because of the buffs it grants. Like all other Infinity Stones, it required that you wear the Dwarven Gaunlet alongside the stone to not be overloaded causing massive damage over time.

Trivia

 * The way the Soul Stone was obtained was reminiscent of how Thanos, the Mad Titan from the Marvel franchise obtains the Soul Stone in Avengers; Infinity War, by sacrificing his daughter Gamora.
 * The tooltip was also a reference to this moment in the movie, being the line spoken by the Mad Titan to Scarlet Witch after she had sacrificed Vision to stop Thanos.