Mercury rules 10th and 1st house is in 12th house in Leo

When Mercury, the planet of intelligence, communication, and mental processes, is placed in the 12th house in the sign of Leo, it can have both positive and negative effects on an individual's life.

On the positive side, this placement can indicate good communication skills in spiritual and mystical matters, such as meditation, yoga, and other contemplative practices. It can also give a strong imagination and creative mindset, making the individual adept in the fields of art, literature, and drama.

However, on the negative side, this placement can make the person prone to secretiveness and deceitfulness in communication, leading to misunderstandings and conflicts with others. It can also bring about a tendency towards isolation, seclusion, or a feeling of being misunderstood by others.

Overall, individuals with this placement of Mercury need to work on balancing their inner world with their outer communication and try to be honest and straightforward in their dealings with others. Developing spiritual practices can help them channel their imagination and creativity in a positive direction.