Complex sentence: The 2nd building, a 2 level open air structure was opened in October 2015 upon the opening of the 2nd building, the mall was re-branded as Vista Mall Antipolo.
Split into simpler sentences: The 2nd building, is a 2 level open air structure and was opened in October 2015. Upon the opening of the 2nd building, the mall was re-branded as Vista Mall Antipolo.