The wall above Audi of Hong Kong is so gigantic it visually consumes their dealership. BMW clearly understood that, buying the space to use for a gigantic middle finger-like billboard over their German competitor. The billboard wars just went global.
This whole tête-à-tête started last April when Audi put up a small billboard in California that said "Your move, BMW" with a picture of the Audi A4. BMW fired back with a giant picture of an M3 with the word "Checkmate" above it. Audi re-responded and that was the end of it until now.