The Dragonball is an Expert Mode-exclusive pet summoning item obtained from the Treasure Bag dropped by The Dragonfolly. It summons a small spherical Dragonfolly to follow the player. The pet will hop in place instead of automatically following the player, but will inflate and rapidly spin towards the player if they travel far enough from it.
Equipping this pet will passively change the name of The Dragonfolly to "Blunderbird". and the Draconic Swarmers to "Blunderling"s. On top of this, there is a 1% chance that either can spawn with the name "Bumblebirb". Unequipping the pet does not revert these effects, and the only ways to revert them are re-entering your world, equipping the Docile Pheromones, or enabling the "Disable Dragonball Easter Egg" config.
- Calamity's boss health bar will display The Dragonfolly's name as "Blunderbird the The Dragonfolly" or "Bumblebirb the The Dragonfolly", instead of just Blunderbird/Bumblebirb like when hovering over the boss.
- The pet is a reference to an image of a tiny, round version of a removed boss known as 'Bumblebirb', slowly vibrating quicker until it explodes.
- The item is also a reference to the television series Dragon Ball Z.