Knut/Series

Season 1
Knut attacked Stella in "An Unexpected Event" in order to steal her ring for his mistresses. When Bloom discovered them she tried to help Stella and used her first spells on him and his ghouls.

When Bloom returns to home with Stella, explaining the situation to her parents, Knut returns to the Trix. He reports of his progress that ended in failure. Though his mistresses were furious at his failure, he redeemed himself by telling them his new plan: using a hunter troll to hunt them down.

He returns to Gardenia with his troll and ghouls, trashing Bloom's house in another attempt to steal the ring but failed again thanks to the intervention of the Specialists. He escaped and his troll was captured.

In the second episode, he was in Magix City trying out new glasses when the Winx walked by. He runs out of the glasses store and alerts his mistresses. When Bloom was discovered eavesdropping on them and she was frozen, her friends came to rescue her and Knut was ordered by the Trix to attack them but failed once more.

In "The Black-Mud Swamp", he alerts the Trix that his captured troll will be taken to police by Red Fountain's Specialists. The Trix, particularly Stormy, feared that the troll will snitch on them and proceed to eliminate it.

On the day of Stella's "date with Prince Sky" and when she was acting strangely, trashing the Winx's apartment and escaping through the window after calling Bloom a thief, the Winx decided to find the real Stella. In disguise, he tricks by giving them the directions to the Black Lagoon, Stella's supposed date place. After the girls successfully find their way, he leads them inside, the door closes on them and he runs down the staircase and disappears. When the Trix finally reveal where Stella is and their goal, Knut is returned to normal by Darcy.

In "Mission to Cloud Tower", Knut wakes up to a loud explosion caused by the Trix's attempt to take the ring's power but failed. He went back to sleep when Stormy casts a spell to make him forget about it. After that, he is ordered to clean up the mess and complains about it. He leaves the room when the Trix call him to meet up with them.

In later episodes, when the Trix finally gain the Dragon's Flame and assembled the Army of Darkness, he realizes how dangerous they are and fearing for his life and the good of the magical dimension he joins the other magical schools to defend it.

Season 2
In "Rescue Misson," he meets Aisha as she walks out of the infirmary. She is scared by him.

In "The Mysterious Stone," he is the DJ at the party in Alfea.

In "Race Against Time," he gives Oleana ice cream in the hallway.

After the defeat of Darkar, Knut can be seen attending the celebration party at Alfea where he is seen arm wrestling Codatorta whom he completely loses to.

Season 3
In this season, after the princess ball when Stella is turned into a monster by Chimera, he develops a crush on her monster form, hearts can be seen around him and he begins to float in the air. And when she is talking about Brandon, he thought she meant himself and tried to "comfort" her. Although, Stella instead gave him lessons on how to be proper in order to court a lady. He tries doing proper postures, in a strange way, before falling onto the floor, Stella then says goodbye to him when Flora tells her they are ready to depart for their mission.

Season 6
Knut appeared in a flashback when Stella recognized Gardenia Park, where she first met Bloom.

The Fate of Bloom
Knut attacked Stella in order to steal her ring for the Trix. When Bloom discovered them she tried to help Stella and used her first spells on him and his ghouls.

When Bloom returns to Gardenia with Stella, explaining the situation to her parents, Knut returns to the Trix. He reports of his progress that ended in failure. Though the Trix were furious at his failure until he mentions there was a very powerful fairy that came to Stella's defense. This powerful fairy intrigues his mistresses and inquires him more about the this fairy.

He returns to Gardenia with his troll and ghouls, trashing Bloom's house in another attempt to steal the ring but failed again thanks to the intervention of the Specialists. He escaped and his troll was captured.

Battle for Magix
When the Trix finally gain the Dragon's Flame and assembled the Army of Darkness, he realizes how dangerous they are and fearing for his life and the good of the magical dimension he joins the other magical schools to defend it.