**Chapter 17: The Castle Breach**

The Toad's frantic cry sent a ripple of urgency through the trio. Peach was already on her feet, her expression grim. "Let's go," she said, leading Mario and Luigi towards the castle. The three of them rushed through the garden, the Toad scurrying alongside them. As they approached the castle, the sound of clashing steel and the shouts of Toads grew louder. Peach's pace quickened, her long strides eating up the distance. "What seems to be happening?" she demanded, her voice carrying over the din. The Toad panted, struggling to keep up. "I-I was on patrol, Your Highness. I saw a group of Koopa Troopas sneaking into the castle through a hidden entrance. They must have been let in by... by the traitor." Mario's face set in a determined scowl. "We'll deal with them soon enough." As they burst through the castle gates, a chaotic scene unfolded before them. Koopa Troopas clashed with Toad guards, while other Koopas rampaged through the corridors, smashing furniture and overturning tapestries. Peach rushed towards the nearest group of Toads, who were pinned down by a cluster of Koopas. "Fall back!" she cried, drawing a small parasol from her dress. With a few swift swings, she sent the Koopas flying. Mario and Luigi charged into the fray, their jumping and hammering skills sending Koopas crashing to the ground. The Toads, emboldened by the royal family's presence, rallied and joined the fight. As the battle raged on, Peach spotted a familiar figure amidst the chaos – one of her most trusted advisors, Toadbert. He was frantically waving his arms, shouting orders to the Toad guards. Peach rushed over to him. "Toadbert! What's happening? How did they get in?" Toadbert's eyes were wild. "Your Highness, I... I don't know. One minute everything was quiet, the next, Koopas were pouring in everywhere. I think... I think it's the traitor. They must have opened the secret door." Luigi's face darkened. "We need to find that door and close it before more Koopas pour in." Mario nodded. "And we need to find that traitor. Now." Peach's gaze locked onto her brother's. "Agreed. Let's move. We can't let Bowser take over our castle." The trio set off, navigating through the battle-scarred corridors, determined to uncover the secrets behind the castle breach and bring the traitor to justice.