The Calamity Box is a magical relic that can be use for teleporting to other worlds that supposedly originated from Amphibia.
The Calamity Box is a golden music box with images of a frog in the tropical woods and three mystical gems and an engraved sun design behind them.
Though its unknown how this box was made, but according to King Andrias, his ancestors used this box to travel to other worlds. After some period of time, it had been supposedly destroyed but somehow remained on Earth where three girls; Anne, Sasha and Marcy had stolen it from a thrift store and soon opened it which instantly send them all to Amphibia -- Anne was transported to Wartwood Forest, Sasha to Toad Tower, and Marcy to Newtopia. In the process, the three gems on the chest lost their power and became uncolored, with the power likely going to each of the three girls (itelligence for Marcy, heart for Anne, strength for Sasha).
According to one of Hop Pop Plantar's books on the Calamity Box itself which described as extremely dangerous; because of this Hop Pop feared the Box so in "Bizarre Bazaar" he buried it near a tree next to the Plantar Farm and lied that he sent it to some "contacts". Upon transportation to Amphibia, the three gems on the box cover lost their power and likely got transferred to the girls, giving them superhuman powers according to each gem, evidenced by having their eyes flash the color of the gem they're associated with.
In order for Anne, Sasha, and Marcy to get back home they need to power up the three gems on the box by taking them to three different temples. Unfortunately, the box is still buried which Anne is unaware of, and Hop Pop lied and said it's with his "contacts". The box resurfaced in "After the Rain". The green gem was charged in "The First Temple", and during that moment, Marcy likely lost the power the gem gave her (evidenced by the glow draining from her eyes when the gem charged). Anne did the same in "The Second Temple", but she left before the blue gem was completely charged thinking her friends were in danger, leaving her with a half charged gem Then Sasha in "The Third Temple" with Her power gone as well. In "True Colors, Anne, saddened over Sprig's apparent death, received powers from the blue gem which she used to fight King Andrias before she was reunited with Sprig.
- Calamity is defined as "an event causing great and often sudden damage or distress; a disaster", which further implies the box to be dangerous.
- The color of the gems stones, green, blue and pink are the same colors as the Powerpuff Girls.
- A real-life version of the box appears at the 2019 D23 Expo. It is presented by Matt Braly, who then lets Kermit the Frog have a look at it, but advises him not to open it. However, Kermit gives in to his temptation and gets teleported to Amphibia. He comments on the journey being "faster than taking the 5 freeway" due to less traffic.
- The colors of the gems in the box can be seen in The Owl House episodes "Escaping Expulsion" (as potions in the basement of the Blight Manor) and "Echoes of the Past" (as graffitis painted on Hooty). In both episodes, the object with blue color is only half full and partially seen, respectivelly, reflecting how Anne's blue gem is only partially charged.