According to himself, the Soul Stone chose Adam Warlock as its wielder. He used its power to keep the Annihilation Wave at bay from a sanctuary called Magus City. However, Magus City was no simple sanctuary, as Warlock had also used the Soul Stone to control and influence the actions of every single one of its inhabitants. Warlock used the Stone additionally to keep a giant behemoth bug under his control. With the power of the Stone, Warlock was able to sense the Bakian Clan's arrival to Magus City in order to retrieve the Soul Stone as part of their hunt for the Infinity Stones. When they encountered Warlock and he denied to give them the Soul Stone, he deployed his Knights of Xandar so the visitors would not just leave empty-handed, but they wouldn't leave at all