Mars in 11th House synastry relationships are established between people that have a clear social connotation when both parties are actively involved in social life. The partners inspire each other to be active, which allows them to achieve what they want in all spheres of their joint life (scientific and intellectual, educational, socio-political, research, etc.).
In a negative scenario, the partners can use friendly relationships for personal selfish purposes out of mercantile considerations, which becomes the cause of contention and omissions. The “Martian” personality may strive to dominate, showing even authoritarian behavior in organizational activity which, of course, distresses the Eleventh House individual who considers their partner intellectually impractical and eccentric.
On the other hand, the Eleventh House person puts forward original creative ideas and organizes the disciplined purposeful activity of the “Martian” one. This allows the partners to work quite fruitfully together, achieving their goals and objectives.
from F. Sakoyan, L. Ecker
Mars in 11th House Synastry Explained
When you see a Mars in 11th House synastry partner in a group, you will undoubtedly notice him: he will probably seem to you very energetic or (if you don’t like his behavior) extremely aggressive. However, in other situations this initial impression may not be confirmed. In a group, you will perceive him either as a rival or as a workhorse to whom you should entrust the most difficult duties: for your own benefit, and for the glory of group at large. However, the opposite may well happen: the Mars in Eleventh House synastry partner will load you very thoroughly, and you, in a strange way, will not resist, especially if you feel that the partner is transmitting the will of the group egregor.
Your participation in any informal group will not go unnoticed by this partner as she will either want to energetically engage in its work, or she will sharply jealous of you and may even pose significant obstacles for you to participate in group activities. In both cases, at first you may not resist, but if the Mars in 11th House synastry partner interference in your group programs inadequately, she will receive a return blow from the group egregor, the strength of which may be great.
In a bad relationship, a Mars in 11th House synastry partner can spend a lot of energy in order to deprive you of all your friends, but when your Eleventh House turns into the Twelfth (complete imprisonment, metaphorical or actual), his power of influence on your circumstances can drop sharply, and then your relationship will suddenly change or even break off … On the contrary, in a good relationship and the development of some tolerance for your friends and your common affairs with them, the partner will find that they infuse him with considerable strength and energy.
from A. Podvodny