Lucian and hitting "marked" targets
Relatively new to LoL and been playing Lucian and have a question about the Ardent Blaze ability.
Reading about it, I see that Lucian gains movement speed after hitting a "marked target" for 1 second.
What I can't figure out, is what it means when a target is marked, or maybe I'm missing something in the game.
I get that "marking a target" is using "g + left click", but I know that I've just fired the ardent blaze into a pile of minions before and gotten the speed buff. And I didn't "mark" anything. Any ideas what is going on?