Gloomix is the negative version of Charmix and has the same power level.
The Trix were given this power by Lord Darkar, in the episode "Up To Their Old Trix" from the second season. It is unknown if witches can obtain the Gloomix by themselves, as the fairies does with the Charmix or just if another evil being gives them this power.
Also, same as the Charmix, the Gloomix gives the witches extra power in places where magic is limited. Apparently also this item allows witches to merge into one being, as seen in the last episode of the second season, when the Trix becomes in Megatrix.
It is a necklace or bracelet, whose color depends on the power of a witch may possess.
- Icy: a gleaming blue necklace.
- Stormy: a gleaming red-violet bracelet on her right arm.
- Darcy: a gleaming purple bracelet on her left arm.