The Astrology website says, The main and foremost chart ruler is the planet that is the primary ruler of the sign on the ascendant and this planet represents you.
I am Pices, However... The chart says I am ascendant for Leo. And I was trying to match up my ascendant sign with what's on the website, right? Like Chart Ruler conjuncts with X planet, But my Ascendant sign, Leo, is only found on the True Node. What does that mean?
Ehm.. I do not understand your question.
But its simple. Your chart ruler = the planet that correspondents with the sign on your ascendant.
You are ascendant leo so your chart ruler is the sun.
Now read about the planet (and the house its in). The true node has to do with fated things or something else for so far I understood, and there is no description given of it on the website, so I guess you'd have to ask someone else for that.
You have a ruling sun in pisces, unaware of your house (you should not feel the need to give such information here). But your Leo ascendant gives you a proud, generous nature. You are fiercely competitive and flattery will get you everywhere, loves to be center of attention (unless other planetary affects this) and may have a natural leadership ability (look at the house, typically of a spiritual nature because of the ruling pisces). You are empathetic, intuitive and caring with the ruling pisces.
Though, you must look at the house and the other aspects as well. I have a ruling sun in pisces too. Although I may have a caring side to my personality, I also have another where I can appear as a ruthless, apathetic, sadistic and cruel person. It's important to take all of your planets, signs and houses into consideration. Some of the alignments either strengthens or weakens the nature.
Hail Satan!!!