Nowadays, Scorpio is ruled by Pluto, but back in the Hellenistic astrology days, it was actually ruled by Mars. That said, Mars feels right at home in Scorpio, and it makes sense—Scorpio is the sign that rules sex, and Mars is definitely a passionate planet.

Then take Pluto, the planet of transformation and rebirth, and we start to get a clear picture on how having a Scorpio Mars results in intensity and unmatched depth.

As astrologer Desiree Roby Antila previously told mindbodygreen, folks with Mars in Scorpio are relentless, with an ability to get through, around, over, and under any obstacle. “They have a really strong drive, but again, they’re fixed, so whenever Mars is in a fixed sign, it tends to make the person pretty stubborn,” she notes.

This can look like having a hard time letting things go, holding grudges, being vengeful, etc., which is telltale Scorpio energy. They also have a tendency to push themselves to the point of burnout, which is something to watch out for.

And according to astrologer Molly Pennington, Ph.D., a Scorpio Mars placement will likely fly under the radar with an air of mystery. “People might just walk up to them not knowing that they’re dealing with a Scorpion—and it’s about to sting,” she explains.

This is all part of the Scorpio Mars strategy of protecting and guarding itself against vulnerability. “They have this deep, emotional side, almost like wars of the heart that are deep down underneath it all,” Pennington says, adding that those wars are often long lasting, and they bring a “battlefield” mindset into all areas of their life.

Take Taylor Swift as a classic example of Scorpio Mars energy. She has a Scorpio Mars, and her insistence on rerecording all of her music to get the rights under her own name is a prime example of this placement’s willingness to win at any cost.