<P> Agravaine de Bois (portrayed by Nathaniel Parker) was the brother of Ygraine and Tristan de Bois and the uncle of Arthur who appeared in the fourth season . Though he was supposedly in Camelot to act as an advisor to Arthur, Agravaine was really there to help Morgana in her attempts to seize the throne . Holding Uther responsible for the deaths of his siblings, Agravaine placed a charmed necklace on the dying Uther's neck in "The Wicked Day" that would ultimately be responsible for the king's death in that episode . </P> <P> Throughout the fourth season, Agravaine influenced Arthur heavily in matters of state, even encouraging the young king to go against his own instincts and wishes, such as killing the king of another kingdom who had been raiding inside Camelot's borders and distancing himself from Gwen in the episode, "His Father's Son". However Morgana often has doubts about Agravaine's abilities throughout Season 4 and is often seen threatening him and he in returns attempts to pacify her and assure Morgana of his abilities . Agravaine kept his cover as a seemingly loyal kinsman to Arthur until the penultimate episode, "The Sword and the Stone, Part One", when he cleared the way for Morgana and the warlord, Helios, to invade Camelot, even joining in the fighting during the battle . After Camelot was secured, Agravaine led a group of warriors in pursuit of Arthur and Merlin, who were fleeing to Ealdor . In the fourth - season finale, "The Sword in the Stone, Part Two", Agravaine was chased into a series of caves by Kilgharrah . He hunted Arthur in the tunnels, but was baited into chasing Merlin towards a dead end . Here Merlin reveals his magic and throws aside Agravaine and his men . Agravaine survives the initial attack and realises Merlin must be Emrys, the sorcerer Morgana has dreamt of . He laughs in shock and tries to deceive Merlin with words of praise so he can stab him, but Merlin sees through the ruse and kills Agravaine with a second attack . </P> <P> Along with Kilgarragh the Great Dragon, Aithusa is the only other living dragon left in existence . She first appears in the episode "Aithusa" when as an egg, she is rescued by Merlin from Jules Borden in the Tomb of Ashkanar . Due to his powers as a Dragonlord, Merlin is able to hatch her, and her status as a White Dragon is taken as a sign of good fortune by Kilgarragh . However, this changes when she heals Morgana in "The Sword in the Stone: Part 2". In "Arthur's Bane Part 2", she is revealed to have been imprisoned for two years with Morgana by Sarrum of Amata, and the trauma of the imprisonment was such that she is left unable to speak and walking with a noticeable limp . The episode "The Hollow Queen" also reveals that as Aithusa grew while imprisoned by Sarrum, the pit she and Morgana were housed in became too small for the growing dragon, and it caused her to become deformed, twisted and stunted in her growth . She is revealed to be perhaps the only being Morgana cares for, and is very much loyal to her . Morgana cares so much for Aithusa to the point where she willingly let Sarrum imprison her to prevent harm from coming to Aithusa . She participates in attacking the forces of Camelot on several occasions in Season 5, and it is only Merlin's powers as Dragonlord that prevent her from killing him and his allies . She also aids in forging Mordred's sword to aid him in killing Arthur . At the Battle of Camlann, she participates in the battle itself until Merlin drives her away, though her further fate is unknown . Aithusa seems to be based on the white dragon that represented the Saxons in Arthurian legend, and is noticeably small compared to Kilgarragh, only being as large as a wyvern at around 6 or 7 feet long . Her small size is again, likely the result of her growth being stunted by imprisonment in Sarrum's dungeons for a long period of time . </P> <P> Alator also known as Alator of the Catha . (portrayed by Gary Lewis) was an enigmatic, magical warrior and priest who briefly allied with Morgana in the episodes, "The Secret Sharer" and "the kindness of strangers". in the episode "The Secret Sharer" Seeking the true identity of Emrys, Morgana engaged his services in exchange for the healing bracelet Morgause had given her in the second season . Alator and his follower then kidnapped Gaius and proceeded to torture him for information about Emrys . When Gaius inevitably gave in and told Alator Emrys' true identity as well as the prophecies about him, Alator switched sides, rescuing Merlin from Morgana by knocking her out . After that, he tells Merlin that he knows Merlin's plans to make a better world, and that he would gladly give his life for it . He did . Captured by Morgana three years later in the episode "the kindness of strangers", Alator refused to reveal Emrys' identity . Morgana used magic to break his neck, and the noble priest died . his servant, Finna also dies protecting the identity of Emrys (Merlin). </P>

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