Can attract enemies nearby to open it, then:
• 7/8 chance to make the enemy opened it become random champion, then spawn another Pirate Chest at random position.
• 1/8 chance, or the enemy opened it cannot become champion / is already champion, explode all Pirate Chest in the room.
The design of the Pirate Chest, to a certain extent, references to the removed mechanic from Identity V. In the Lakeside Village, there once could spawn chests by the sea, offering great bonus for both Survivors and Hunters.