Scorpio is the middle of autumn, fixed and water. The season is settled and the light is unmistakably going.
Mars ruled it for two thousand years before Pluto's discovery in 1930 reassigned it. Both attributions survive in use, and this site lists Pluto as ruler while the traditional scheme gives Mars — a disagreement worth knowing about rather than hiding.
The traditional appetite for what is concealed matches the season: this is the part of the year where things are stored, buried and kept.
Traditionally attributed
Depth, control, loyalty, and an appetite for what is withheld.
Listed because it is what the tradition says, not because this site can check it. Everything above this line is geometry; everything in it is convention.