A chain-lightning-infused box calls the needed storm goddess but also summons a second god because deep-floor use produces unpredictable extras.
Mordecai carries the device away from the exit and activates it far enough to buy preparation time without losing the gods' attention. Infusing it with a chain-lightning potion successfully biases the result toward storm deities.
The box summons both Dodola and Adad. Odette notes that additional gods sometimes appear this deep, making the result dangerous but initially useful because either could activate the storm puzzle.
A compact magical cube crackling with stored chain lightning beneath acid rain.
The box creates the divine encounter required for the party's final exit puzzle.