Seven Kin of Purgatory

The Seven Kin Of Purgatory (煉獄の七眷属 Rengoku no nana kenzoku) is the strongest team of Grimoire Heart Guild. It is formed by seven mages who have been personally trained and raised by their guild master, Hades. Each of them has his/her own unique set of abilities. Because they each possess knowledge of at least one type of Lost Magic, Hades considers them unbeatable. Even Yomazu, a mage who critically injured former S-Class mage Gajeel, said he was nothing before them and stood no chance of victory if he were to fight one of them. They are the main forces of Grimoire Heart and are the primary reason why it is the strongest Dark Guild.

Mages

 * Ultear - A beautiful, manipulative, and mysterious woman whose primary magic allows her to manipulate the "time" of inorganic objects, leading to her being known as the "Time Mage". She was a misbehaving member of the Magic Council who had previously encountered Fairy Tail members under the guise of Zalty. She defected from the Council and destroyed its main headquarters, later revealing that her true allegiance was to Grimoire Heart. She completely repaired the Grimoire Heart airship from destruction during its battle with Makarov. After she arrived at Tenrou Island, she began running towards where she thought Zeref was. She has finally encountered him, though he is extremely angry at her and the rest of Grimoire Heart.
 * Zancrow - A psychotic and violent God Slayer whose magic of black flames makes him superior to standard Fire Dragon Slayers. His magic can supposedly turn his enemies into ash. After he arrived at Tenrou Island, he confronted Natsu and came out at a great advantage in their battle because Natsu could not consume Zancrow's black flames (and therefore was not immune to them), while Zancrow could easily eat Natsu's flames; as a result, Natsu was blasted far away from the battle next to a wounded Makarov. In their second confrontation, Natsu actually landed several hits on him, but he quickly regained the upper hand and nearly killed Natsu by trapping him in a sphere of black flame. However, Makarov intervened in the battle to aid Natsu, allowing Natsu to use some quick thinking and nullify his own flames so he could eat Zancrow's black flames. Zancrow was then heavily wounded by a massive flame attack that combined both his flames and Natsu's. Lying on the ground, but still conscious, Zancrow could still be considered the winner of the battle as Natsu collapsed shortly afterward from his injuries.
 * Caprico - A tall, emotionless goat-like member who has authority over Yomazu and Kawazu. He possesses a recall magic that allows him to rapidly deploy troops to the battlefield via magically storing them away and then raining bubbles containing the troops down on a chosen location (Tenrou Island), which he was able to do from the sky with the help of a jetpack. He is also a powerful and agile physical combatant who primarily uses kick-based attacks. After he landed on Tenrou Island, he confronted Lucy, Cana, Loke, and Gray, and quickly gained the upper hand in the fight thanks to this physical prowess.
 * Rustyrose - A stoic, bespectacled male dressed in fancy clothing. After he arrived at Tenrou Island, he confronted Elfman and Evergreen. His abilities are currently unknown.
 * Kain Hikaru - A large, overweight, and clumsy man with a speech disorder. When the Grimoire Heart members dropped down on Tenrou Island, Kain fell face-first onto the ground, being rendered unconscious in the process. As such, he hasn't been able to confront any Fairy Tail members yet. His abilities are currently unknown.
 * Meredy - A petite, cute, and timid young girl. After she arrived at Tenrou Island, she confronted Erza Scarlet and Juvia Loxar. Her abilities are currently unknown.
 * Azuma - A stern, muscular man, he uses two discrete magics in battle that complement each other well: one allows him to produce deadly explosions at will, and the other allows him to manipulate roots and trees, allowing him to ensnare opponents, shield himself from harm, and hide from plain sight via merging into trees. He was the first of the seven Kin to appear on Tenrou Island, where he quickly defeated Pantherlily, Wendy Marvell, Mest Gryder, and Charle with his explosive magic despite their coordinated teamwork. Afterwards, he left the area, only to eventually come across Mirajane and Lisanna after the rest of his guild had arrived on the island. When he found out that the "Demon Mirajane" was one of his opponents, he requests a formal battle with her. Because she did not respond to his request, he traps Lisanna in a set of roots that would detonate in three minutes time, with the condition that she could only be saved if he was defeated in time. This results in the fight against the "Demon Mirajane" that he desired. As he fights Mirajane, who lacks magic to sustain her Satan Soul and who constantly loses focus because she checks back on the timer, he retains the upper hand in the battle with the combination of his two magics. As the timer nearly runs out, Mirajane, who realizes she can't win, runs back to Lisanna, much to Azuma's shock, and shields her from the blast, leaving her status unknown. Upset at the loss of a strong opponent, he walks off once more.