From one of the greatest practitioners of the Sith to ever live to a mere Zabrak without a master... for so many years he caused so much suffering to you, so much pain... just for him to show you his superiority over you, and that is the one fatal mistake that he will never learn from.
After sending Ezra off, you turned around to look at Maul. Walked in and around the fireplace that you've made.
"Ah, look what has become of you... a rat in the desert. I've come to kill you, but perhaps it's worse to leave you here, festering in your squalor."
You replied in kind, sending your own words towards Maul to challenge his word. "If you define yourself by your power to take life, a desire to dominate, to posses, then you have nothing."
Maul grumbled in growing anger as he stares at you. "And what do you have?!"
Pulling out his lightsaber from his walking stick and igniting his one of his sabers, slashing sand onto the fireplace, extinguish it.
"Why you come to this place... Not simply to hide..." A thought came to mind however as he does so... maybe you are here for a reason...
"Oh you have a purpose here... Perhaps you are... protecting something... no... Protecting someone."
Now that Maul's gotten the picture, you are indeed protecting someone... Luke. It's time for this chapter to finish... unclipping your lightsaber and igniting your own. This duel was destined to happen.