The Evil gang is the family of thieves. The mother, Alga (アルガ), acts as the leader while her two sons Dios (ディオス) and Nortis (ノティス) are the enforcers. The daughter Terra (テラ) often acts as a decoy to make people lower their guards.
Ys V: Kefin, The Lost City of SandEdit
Adol first encounters the Evil gang when he encounters Terra and her brothers in the forest. Terra pretends to be a damsel in distress and tricks Adol into fighting a boar. After Adol defeats the beast, they reveal their identities and declare their intention to find all the crystals before he does.
Adol encounters them again in Nedo's Cavern. Just as Adol finds the water crystal, the Evil gang appears out of nowhere, takes the crystal, and runs off. Adol notifies Dorman of the theft and Dorman replies that it won't take very long to catch the thieves.
When Dorman reveals his true colors, Adol find them again in the prison underneath the village of Xandria. They break out of the prison, swearing revenge on Dorman. As Dorman is holding Niena a hostage, Adol is forced to give up all the crystals and gets taken to the island where the ritual is being held to break the seal on Kefin. The Evil gang arrives at the island just in time to reveal that the water crystal that they handed over to Dorman was a fake. Enraged, Dorman uses his own alchemy and tries to destroy Adol and the Evil gang but Adol defeats him after a grueling battle. Unfortunately, Rije, the true mastermind, takes the real water crystal from the Evil gang and breaks the seal on Kefin, causing the ancient city to appear again. As they wish to find treasure in Kefin, the Evil gang follows Adol to Kefin.
Upon the arrival at Kefin, the Evil gang goes off on their own to look for treasures. Adol joins the resistance against Kefin's oppressive regime and goes to the tower to rescue Niena. At the top of the tower, Adol finds Kefin's commander Baruk who is keeping her hostage. The Evil gang manages to rescue her while Baruk is busy taunting Adol and Adol defeats Baruk in the ensuing battle.
Unfortunately, the Evil gang, along with Niena, are caught by Kefin's soldiers and get locked up in prison. They are about to be sacrificed by Rije in the ritual to maintain the power of the Philosopher's Stone but Adol comes to their rescue. After saving them, Adol defeats Jabir, the alchemist who was controlling Kefin from shadows, and destroys the Philosopher's Stone. The destruction of the Philosopher's Stone causes Kefin to disappear and Adol and his allies, along with the citizens of Kefin, manage to escape from Kefin successfully.
As Adol prepares to leave Xandria in search of a new adventure, he runs into Terra one more time. She tells Adol to watch out for her since in five years, she will grow up to be a beautiful woman...a word she keeps when she encounters him at sea three years later.
- In the original concept, more light was shed on the Evil gang's past and motivation. Alga's husband was a low ranking general from the Eastern kingdom of Orietta. Unfortunately, after failing the mission, he got executed and the family were thrown out in the streets. In order to survive, they had to turn to the life of crime. By the time of the game, the Evil gang was manipulated by Rije to search for the crystals. Their motivation for trying to reach the city of Kefin was to start fresh and lead honest lives. As Terra's father is revealed to be Ladock the pirate in Ys VI: The Ark of Napishtim, one may assume that this backstory is no longer canon.