“Dan? You came! How did you find me?”
“You ‘called’ me and I’m here to answer it. Now, allow me to show those beasts what I’m made of!”
I take your point about calling his evil future self "Phantom," but I'd like to make a case for Dan. As Tumblr user Lightning Streak pointed out, while Danny is a short form of Daniel, a Hebrew name meaning "God is my judge," Dan can be a separate name meaning simply "He who judges." It takes God (and goodness, and deference to authority) out of the equation and shows how Dan is making his own rules. Of course, he's not God, so he's nowhere near as benevolent or just in his judgments...