This is the second of a series of gameplay videos by none other than the Sparkplay dev known by the name Shazbawt. It features several developers running the then-brand new dungeon The Down Below. In this video, the group fights the boss Serrano the Master Chef.
Because it was likely made by a former Sparkplay developer and features several of them, this gameplay video can be considered in the realm of 'semi-official' as a 'developer test-run' or 'developers just having fun'.