Man, that is a bummer... Seems like the ESC just dead shorted the packs or something as soon as they were plugged in.

Were the packs pre-wired with connectors, or did you have to install them? What kind of connectors?

Does the + and - line up from the packs to the ESC right?

What kind of E-Maxx? 3906 or 3905? EVX-1 or EVX-2 ESC.

I would contact the ebay store immediately and see what they say. Post some pics of the carnage!