Summoned Souls are summoned from the River of Souls during the fight with Cerberus, indicated by it howling Aaarrrooooooo. The souls colour and equipped weapon coordinates to their attack style: red/sword is melee, green/bow is range, and blue/staff is magic.
The order in which they appear is randomized, but they always attack from west to east. Thus, players can predict the order of attack the souls will do, and prayer flick as they attack to mitigate their damage. If an incorrect protection prayer is used for the attack, then 30 damage is dealt regardless of worn equipment. If the correct protection prayer is used, then 30 prayer points are drained instead. Using a spectral spirit shield will reduce the prayer drain by 50%.
Once all three finish their attack, they return to the River of Souls, wailing quotes such as "Join us.", "I obey.", and "Steal your soul."
- Prior to an update on 8 October 2015, Summoned Souls did not wield weapons. This was added so colourblind players would have an easier time distinguishing the combat style the soul would use against the player.