In a verdant expanse of the Enchanted Wildwoods, Tenzin, a wizard of air, and Aarav, a sorcerer of light, stand on opposite ends of a dense clearing. The forest is wrought with a magical property: sound cannot travel through the air, making it impossible for anyone to hear anything across any distance. In the middle of the clearing stands the Silent Stone, an ancient monolith that has the ability to visually project anything spoken in its proximity into a clear image above its peak, regardless of the sounds being intentionally made for communication or just mere mutterings.

Tenzin and Aarav each holds half of a mystical relic, the Scepter of Unity, which when joined together, reveals the location of a hidden treasure within the woods. Their task is to combine the pieces at the Silent Stone before nightfall, while navigating the magical constraints of their surroundings. However, unbeknownst to Tenzin, a sprite named Elara, possessing the innate power to read minds, has been sent by a rival enchanter to prevent the meeting without directly intervening.

Given this scenario, Elara hovers invisibly between Tenzin and Aarav while the sun gently makes its way towards the horizon. The forest creatures around them carry on with their activities, indifferent to the significance of the events unfolding. With the knowledge that Tenzin and Aarav must reach the Silent Stone to accomplish their quest and that Elara can read thoughts, how can Elara effectively use her ability to thwart Tenzin and Aarav's meeting without them ever realizing her presence, and what steps would she take to do so?
Firstly, Elara needs to understand the mindset and plans of both Tenzin and Aarav. Since she can read minds, she starts by focusing on Tenzin's thoughts. Tenzin is likely concentrating on the path to the Silent Stone and may be forming a strategy in his mind to connect his half of the Scepter of Unity with Aarav's half. Elara notices that Tenzin is planning to approach the stone using a series of hand signals to communicate with Aarav from a distance owing to the sound void in the Enchanted Wildwoods.

Having gained this insight, Elara then shifts her attention to Aarav. Aarav, understanding the limitations of their environment, is likely thinking of ways to visually signal Tenzin, perhaps by using the light his sorcery can conjure, flashing patterns that could carry a message across the clearing to confirm he has his piece of the scepter ready for the joining.

Elara now knows the methods of communication Tenzin and Aarav are planning to use. To impede their progress without revealing her involvement, she can subtly influence their thoughts to mistrust the other's signaling. While Tenzin contemplates his hand signs, Elara implants doubt in his mind about the reliability of Aarav's light signals. She suggests, through thought alone, that perhaps the light patterns could be misinterpreted by creatures of the woods or be reflections of the setting sun, making them unreliable.

Similarly, for Aarav, Elara casts suspicion on any hand signals from Tenzin. She injects the idea that hand signals could be too complex or easily obscured by the foliage and shadows of the forest, possibly causing confusion. She could amplify Aarav's own inner fears that the hand signals might not be a secure means of communication.

Throughout this process, Elara takes great care not to reveal her presence. She ensures that her suggestions in their thoughts seem like their own natural doubts and apprehensions, which would naturally arise in such a silent and visually cluttered environment. Additionally, she does not place any foreign thoughts or ideas that would feel intrusive or prompt Tenzin and Aarav to suspect another being's influence.

Elara's next step would be to intensify these doubts at critical moments. As they draw nearer to the Silent Stone and the sun casts longer shadows, making the visual noise of the forest even more deceptive, she amplifies Tenzin's skepticism each time Aarav attempts to utilize his light communication. Tenzin is convinced that the visual signs from Aarav are unreliable and decides to wait for a clearer signal.

Concurrently, Elara increases Aarav's uncertainty when he catches a glimpse of Tenzin's hand signs through the branches. Aarav's mixture of doubt and the complexity of deciphering the signals in the fading light leads him to hesitate, waiting for a more distinct and confidently recognized sign from Tenzin.

Hence, by inserting plausible doubts into each of their thoughts at key moments, Elara ensures that Tenzin and Aarav are unable to come to a mutual understanding or trust in each other's signaling methods. Each wizard waits for a clearer indication from the other that never comes due to their manipulated misgivings, thus preventing them from meeting at the Silent Stone to combine the Scepter of Unity as night falls. Elara's success lies in her subtle influence -- causing hesitation and mistrust without them ever suspecting her presence or any external tampering with their thoughts.