Circa 2013. A rare sight of it preying upon a smaller snake, presumably a wild snake that fell into its exhibit or it was a specialized live food, since king cobras mostly prey upon other snakes.
This are obviously ptyas korros that was to be fed specifically for the cobras, pretty much this colubrid species are a go-to feeder animals for the king cobras in Indonesian facilities (Like in Ragunan, where they regularly bred this snake).