This is the Looterkings-Skin package called ironically "ProGamer-Pack", as it is a reference to three german Youtubers (Gronkh, Sarazar, SgtRumpel) who are not exactly known to be the best players. Also, they are the partners of Looterkings GmbH, the game-dev behind Looterkings. This skin-Packs are meant as a goodie for the community, presented as a cost-free DLC.