Why have the old man killed by the kids ?
What was the green stuff that blew up the temple ?
Why did they have the servant chase the kid to the green stuff ?
Probably shouldn't post spoilers in this thread. Wouldn't hurt to have a GoT thread to discuss the above though.
No spoilers here, unless you haven't seen the finale.
Why have the old man killed by the kids? The new maester used the weapons he had: his little "birds". (my guess)
What was the green stuff that blew up the temple?The explosive material was mentioned - and used - before. The reference was to the former mad king Targaryan, who had the city's underground laced with the stuff, so he could watch the city burn if it turned against him. Tyrion Lannister used the stuff to defend against the Barathion fleet two or three seasons ago.
Why did they have the servant chase the kid to the green stuff?Poetic justice and dramatic effect, one supposes.