Sparks (also known as Domino in the RAI dub) is the original home planet of Bloom.
Society
Sparks is a planet run by monarchy. It is ruled by King Oritel and Queen Miriam. Their current princess is Princess Bloom. Dafne used to be a princess until she died.
4kids History
Sparks is the final resting place of the Great Dragon, as stated by the series' legend.
Sixteen years prior to season one, the three Ancestral Witches attacked in their search for the Dragonfire. However, before the witches could steal the power, the guardian nymph Dafne who resides at the bottom of Lake Ethemera, took baby Bloom and sent her to Earth were she could be safe as Bloom was the next guardian of the Dragonfire. Bloom was then found by her adoptive father and fireman Mike in which the flames of the building went completely out after Bloom was picked up.
Bloom later discovered that Sparks was the planet she was born on and raised for a few years until the three ancient witches froze the entire planet while searching for the Dragonfire. It was then presumed a dead planet inhabited by nasty creatures such as ice crabs and giant yetis.
The events of the movie do not apply, that is: have never happened, in this continuity.
RAI History
Sparks is originally called Domino in the RAI version.
Domino is the final resting place of the Great Dragon, as stated by the series' legend.
Sixteen years prior to season one, the three Ancestral Witches attacked in their search for the Dragon's Flame. However, before the witches could steal the power, Bloom's older sister Dafne whose spirit resides at the bottom of Lake Roccaluce, took baby Bloom and sent her to Earth were she could be safe as Bloom was the next guardian of the Dragon Flame. Dafne is assumed to be dead as she has no physical body. Bloom was then found by her adoptive father and fireman Mike in which the flames of the building went completely out after Bloom was picked up.
Bloom later discovered that Domino was the planet she was born on and raised for a few years until the three ancient witches froze the entire planet while searching for the Dragon Flame. It was then presumed a dead planet inhabited by nasty creatures such as ice crabs and giant yetis.
The planet was revived by Bloom and her friends (sans Nabu) in the movie Winx Club: The Secret of the Lost Kingdom. Life returned to Domino after Bloom with the aid of her dead sister Dafne defeated the spirits of the witches and then destroyed the Obsidian Dimension along with Mandragora. As a result, Bloom also reunited her family and finally met her biological parents.
There is absolutely no mention of Domino in season four.
The second movie is assumed to take place in Domino as promotional art shows Bloom frustratedly seated on a throne and surrounded by the Winx Club, her adoptive and biological parents and Sky.
Fauna
Prior to the revival, Sparks was a dead planet populated by ice crabs and yetis. There was also the giant stone bird that guarded Oritel's library in the movie.
After the revival, life returned. Some frozen animals survived the magical ice age. The fauna is presumably similar to Earth's.
Flora
It is assumed to be similar to Earth's.
Renaming
In all other dubs, Sparks is originally called Domino. The renaming of Domino to Sparks is one of the most prominent changes made by 4kids.