Pokémon Mystery Dungeon: Explorers of Sky is an enhanced version of Pokémon Mystery Dungeon: Explorers of Time and Explorers of Darkness released for the Nintendo DS in 2009 developed by Chunsoft and published by The Pokémon Company and Nintendo. As a sister game and sometimes referred to as the definitive edition to the aforementioned games additional features include the addition of the missing Generation IV Pokémon further character development for a few side characters in content known as Special Episodes and a few quality of life improvement for options items and other gameplay related features.