He left active development on the game to form PUBG Special Projects and PlayerUnknown Productions in March 2019.

[4] While trying to save up enough money to buy a plane ticket back to Ireland, he found himself playing video games, particularly the open world survival DayZ mod for Arma 2.

In December 2019, Greene announced a new game called Prologue under a new studio PlayerUnknown Productions, described as "an exploration of new technologies and gameplay.

[14] On December 5, 2024, PlayerUnknown Productions released Preface on Steam, "an immersive tech demo showcasing Melba", an engine developed in-house.

[1] Artemis is intended to be "the culmination of in-house technology that could host millions of players inside large-scale worlds at once.