The invitation is sent by right-clicking the friend's name on the friend list and selecting 'Random Encounter'. To invite friends, they must first be added to the player's friend list. Up to two friends can be invited to join the battle. When the item is used, the player and their summoned friends will gain a 100% damage buff and a damage reduction buff for the duration of the boss battle. The Demon Banishing Order is an item that can be used to enter Heart of the Devil.
If the player interacts with the lantern, they will be teleported to the boss arena and no more lanterns can be summoned until the next day. If the player doesn't interact with the lantern, they can summon more lanterns. The lantern will despawn after 3 minutes. Only the summoner can interact with the lantern. The lantern will randomly spawn next to the character when they perform any Chi-boosting activities, such as fighting.
The big red lantern is used to enter the Heart of the Devil. Each player can participate in Heart of the Devil 4 times a day: once via the Demon Banishing Order, once via the red lantern, and twice by accepting a friend's help request.The player must not be participating in another event.Character Strength ≥ Untapped Potential.
