What does a 4-body stellium (Saturn, Venus, Mercury and the Sun all in conjunction) and in the 8th house mean?

Let us list down the preliminary information based on the details provided

• Saturn-Venus-Mercury-Sun conjunction in the 8th House

Let us look at the observations linked to the information shared

1. 8th House as per the basic chart (which starts with Aries & ends with Pieces) is the Zodiac of Scorpio (ruled by Mars). This is the house linked to life post marriage, in-laws, sudden events, death, surgeries, unseen & unexpected things linked to occult. 8th House is linked to something hidden or below the surface of the earth
2. Sun-Mercury in the 8th House makes the individual through light on unseen things in life through research. Ideal career choices can be – investigate journalism, Scientific Editor, Geologist, etc.
3. Saturn in the 8th House makes someone interested in occult (like Tarot, Astrology, etc.). The placement also tends the person to dig into untalked or new things like substitute for Lithium, Cobalt in Electric Batteries, etc.
4. Venus in the 8th House can give some challenges linked to relationships especially romantic but the individual if they keep an open mind will feel their relationship always in the “happening” mode with no time for getting bored

Also, for understanding the entire impact we need to evaluate the chart completely which can give the better direction.

These observations get stronger during the transit & Mahadasha (main period) of the planet.

Kindly note, the planets (Saturn, Mercury and Venus) should not be combust (being with 10 degrees of the Sun. If this happens the Sun will dominate the 8th house.

Hope this helps

You can read more on different combinations linked to astrology through the following links:

Quora Posts – Lateral Thinking

All the Best

For Paid Consultation – Link

God Bless!