The Fairy Bell is a HardmodeLight Pet summoning item that summons a glowing creature resembling a Pixie, which follows the player and provides light for an infinite duration. The summoned Fairy is either pink, green or blue, the color of which changes randomly each time the player clicks while holding the item.
The spawned Fairy will keep up with walking players, but not players who are falling or using speed-increasing accessories.
If the player is too far away from the spawned Fairy, the Fairy will teleport to the user.
Like the Pixie, the fairy summoned by the Fairy Bell is similar to fairies in the Legend of Zelda series, in which fairies are spheres of colored light with wings. The three colors the fairy can appear as (pink, green, or blue) is also a common theme in the Zelda series, with the colors representing the goddesses Din, Farore, and Nayru respectively.
It could also be argued that the blue Fairy is Navi, the pink one is Tael, and the green one is Saria's fairy.
Despite the fairy buff displaying a yellow fairy and the pixie Enemy on which it is based is yellow, the fairy pet itself never is.
Right-click cancelling the buff appears to behave strangely. Sometimes it will "reset" the buff, resummoning the fairy and choosing a new color, and sometimes it will remove the buff as usual. It is uncertain as to why this happens.
Despite its name, Pixie Dye will actually not make the fairy colored like the Pixie enemy. Instead, using Orange Dye on the Fairy Bell will make it resemble a Pixie.
During a Blood Moon, the pet fairy takes on a yellow color when it is not dyed. This happens no matter what color (blue, pink, or green) the fairy was previously.