Seven Kin of Purgatory

The Seven Kin of Purgatory often refered to as the Seven Kin, was an elite team and was amde up of powerful and elite dark mages and served as the secondary antagonists of the Tenrou Island Arc of the popular anime and manga series, Fairy Tail. It was made up of the seven most powerful warriors and members of the Dark Guild, Grimoire Heart, where they served as the guild's main attack force.

Overview
The Seven Kin of Purgatory was an elite team that was formed at an unknown point of time a few years back prior to the series, it was lead by Ultear Milkovich where she had a few years prior back, ran into a young girl named Meredy and adopted her where she also recruited her into becoming a member of the team and a member of Grimoire Heart as a whole. Eventually, the team grew to be at seven members strong (or eight since Zoldeo was possessing Capricorn the whole time). Eventually in the year X784, the Seven Kin were deployed to Tenrou Island where they had battled with the wizards of Fairy Tail. Despite almost beating them, Fairy Tail managed to turn things around and most of the team became casualties in the Guild War with three members dead, another three defected from the guild all together, and only two known acitve members left.

Strength
The Seven Kin of Purgatory was the most powerful team in all of Grimoire Heart and was also one of the most powerful sub-factions in the entire Balam Alliance. The Seven Kin was responsible for Grimoire Heart's status as the most powerful Dark Guild due to the powers and abilities of all seven members. Ultear, the leader, was capable of manipulating time and Zancrow was capable of Flame God Slayer Magic. The other members were also strong in their own right as well with Azume's tree magic and Capricorn's strength during his time being possessed by Zoldeo. Meredy herself, while being the weakest of the Seven Kin, was still able to challenge Juvia Lockser and Erza Scarlet and hold her ground despite her status in the team.

Azuma and Zancrow were the most notably powerful members of the Seven Kin as they engaged two of Fairy Tail's most strongest wizards, Erza and Natsu, and their strength was shown with Azuma being able to destroy an enitre fleet of Magic Council ships and Zancrow being able to burn away an entire squad of Grimoire Heart soldiers at once. Despite how powerful all seven of them were, they all became casualties in the battle with Fairy Tail with three members dead, another three defecting, and leaving only two survivng acitve members.