In "The Black-Mud Swamp," the Winx and their classmates had to do an exercise there, and the Trix helped the Hunting Troll escape from the Specialists and made him disappear so that he would not reveal anything about their plan to steal Stella's ring and acquire the Dragon's Flame.
In "The Monster and the Willow," Flora moved her experiments here after they outgrew her dorm. The Winx also helped the Undines by defeating the Red Willow that had grown on the back of a Giant Turtle and caused everything that came near the turtle to fall asleep.
In "The Ultimate Challenge," thanks to the location of the swamp which is close to Cloud Tower, the Undines saw the Army of Darkness heading towards Alfea for the final assault of the Trix and went to warn Faragonda and Saladin of the attack at Alfea.
#6: The Swamp Monster
The Black Mud Swamp acts as a major setting to Issue 6 as the Specialists are tasked with traveling there to neutralize any and all nightmare monsters to keep Magix and its schools safe. Meanwhile, the Trix have traveled to the Swamp to collect ingredients necessary for most of their potions.
During their search for potion ingredients, the Trix catch sight of the Specialists and upon realizing that they prefer Alfea Fairies to Cloud Tower Witches, Icy comes up with a plan to reverse that, so she fakes having twisted her ankle, which naturally attracts the Specialists' attention.
As the Specialists surround Icy to check on her ankle, Darcy finds herself unable to bear how easily they were drawn to her, which Stormy quickly teases her about. While the Specialists help Icy to her feet, Darcy approaches Riven, the only one of the Specialists who did not try to tend to Icy's "wound," and starts up a conversation with him. Though he keeps his distance, he seems to be attracted to Darcy's words once she claims that witches specialize in dealing with other types of pain like the pain that comes with being unappreciated despite your worth. As Icy introduces herself to the rest of the Specialists, Riven pursues Darcy to hear more about how she can possibly fix such a thing with magic, but the two quickly come across the skeletal remains of a saurodont in the middle of the path.
Realizing that they may have to combat a nightmare monster, Brandon rallies the Specialists but they are stopped by Stormy, who hopes that they are not about to just abandon them with something more powerful than a saurodont lurking about. That is when Riven volunteers to stay behind with the Trix and keep contact with the rest of the Specialists by radio. This is most likely because he had fallen for Darcy's words and wishes to see if she can truly change his situation around.
Just then, Timmy catches sight of a group traversing the Swamp on the other side of a nearby river and this group quickly turns out to be none other than the Winx who have come to find medicinal herbs essential to their potionology homework. Brandon and Prince Sky try to warn the Winx when Stella catches sight of them but just before they realize what the boys are trying to do, a giant multi-limbed monster emerges from the mud just in front of them!
With no other options, Prince Sky, Brandon and Timmy brandish their weapons and charge at the monster while the Winx transform to properly defend themselves. Despite their best efforts, the monster proves to be almost indestructible as it regenerates any body part it loses whenever it takes a hit.
Meanwhile, Icy and Stormy have become furious over how the Specialists left them behind to defend the Winx and Icy quickly comes up with a plan she believes would prove to the Winx that the Specialists are incapable of defending them. Aware of the dangers that would come with using a spell powerful enough to aid the swamp monster, Icy has Stormy use Riven as the energy source she needs to create a powerful storm that envelops the Swamp.
The storm renders the Winx and Specialists unable to properly combat the monster so they flee to higher ground. However, since Timmy had been snatched up in one of the monster's many hands, the Winx (except Bloom) pool their magic together to get the monster to release its grip as it melts under the torrential rains, giving Prince Sky the opening he needs to swim in and save Timmy. Brandon and Bloom got separated from the group in their escape from a wave of swamp-water and Riven, who is still being sapped of his life energy, is on the verge of death.
Darcy catches this and pleads for her sisters to stop before it is too late. Icy complies and has Stormy end her spell which gives Darcy the opportunity to check up on the unconscious Specialist. Darcy seems oddly defensive of Riven, insisting that he is not like "the others," and claims that she did not want them to waste Riven's potential as she believes that he could become a valuable ally to them. Icy humors Darcy by telling her that Riven will simply wake up with no memory of what happened and tells her that she can stay behind to take care of him if she wants while she and Stormy take their leave.
Meanwhile, Tecna and Prince Sky find themselves unable to get Timmy to wake up and, to make matters worse, their radios have been destroyed thanks to the rain and Bloom and Brandon had ended up stranded on a small island in the middle of the river. With no other choice, Prince Sky notifies Brandon that they will be returning to Red Fountain on foot to get Timmy the help he needs and promises to come back with help. The group begins their trek back as Prince Sky has Musa keep an eye out for solid ground. As she does so, she catches sight of Darcy and Riven alone together nearby and watches on anxiously in hiding as Darcy helps Riven out of the Swamp.
With their friends now out of sight, Brandon asks Bloom if she is alright and lends her his cloak to keep warm when she tells him that she has gotten cold from how damp her clothes have gotten. Since it will take hours before Prince Sky and the others will get help for them, Brandon takes it upon himself to build a shelter that he and Bloom can hide away in from the rain.
A while later, the two are safe under Brandon's make-shift shelter with a fire to keep them warm. Bloom has Brandon come under the cloak with her but before the two of them snuggle up closer, Brandon makes sure that Bloom is alright. Once she confirms that she is, he proposes that they make up from a small fight they had the day before. Bloom agrees to this and Brandon kisses her on the top of her head as she holds him close.
Eventually, the budding couple is found by Codatorta who rescues them and brings them safely back to their respective schools.