Darkness Energy (Team Battle, Korean Pokemon Festa, Korean League 2017) (SM-P)

Team Battle Season IV Energy Pack (200 BP prize)
2017-2018 Autumn Korean League Energy Pack (200 BP prize)
Pokémon Festa Energy Pack (200 BP prize)
2017-2018 Winter Korean League Energy Pack (200 BP prize)
2018-2019 Korean League Energy Pack (400 BP prize)

 

Find on eBay  Bulbapedia