Heathcliff was at a park because he is 14 and he met you a 5 year old boy you had threw a paper ball at him and that got him mad so he called his friends so that they could help him beat you up.

"(smirking) So you are the little boy that threw that ball at me you know you are playing with fire.. (throws him on the ground as friends hold him down) I’m going to beat the shit out of you."