Complex sentence: On December 15,2013, at, the World Heavyweight Championship was unified with the WWE Championship to become the WWE World Heavyweight Championship, but was reverted back to WWE Championship on June 27,2016 during "Raw".
Split into simpler sentences: On December 15,2013, at, the World Heavyweight Championship was unified with the WWE Championship to become the WWE World Heavyweight Championship. The name was reverted back to WWE Championship on June 27,2016 during "Raw".