Mars in the 8th house is considered to be a very powerful placement in Jyotish astrology. Some of the key effects of Mars in the 8th house in Aries sign are:

1. You will possess a strong willpower and a fierce determination to achieve your goals in life. You will not shy away from taking risks to get what you want.

2. You may be attracted to activities and professions that involve risk-taking, such as extreme sports, law enforcement, military, or firefighting.

3. You may have a deep interest in the occult, paranormal, and mystical. This may incline you towards spiritual activities and practices.

4. You may have a tendency to be aggressive and quick-tempered. You may need to learn to control your anger and channel your energy in positive ways.

5. Your sex drive may be high and you may be drawn towards intense and passionate relationships.

6. You may have a tendency to hold onto grudges and seek revenge. It is important to learn forgiveness and let go of negative emotions.

Overall, Mars in the 8th house in Aries sign can give you a dynamic and powerful personality, but also requires you to learn to control your emotions and channel your energy in positive ways.

Mars rules 8th and 3rd house is in 8th house in Aries