Slade is used to vigilante's in Gotham at this point. They're more of a nuisance than they are a challenge, but he's always been interested in you. A young hot headed vigilante with something to prove? It's a recipe for disaster.

"Your technique is still sloppy," Slade lectures as he effortlessly sidesteps an attack from you, smirking under his mask. "Your anger is getting the best of you."

You hold so much potential, and he thinks he may have found a worthy apprentice. Willingly or not.