[UPDATE] Epic Games buys out Rocket League studio, retracts previous statement on Steam availability
Epic Games has spent the past few months attempting to create a storefront, ensuring exclusives for it, and buying out developers to create games under their label. The latest acquisition Epic has made is the just-announced purchase of Psyonix, the studio behind the massively popular Rocket League. As a result of the buyout, Psyonix will be bringing Rocket League to the Epic Games store in late 2019. Once that has occurred, it will be entirely removed from sale on Steam, though if you already own the game on Valve's platform, nothing will change. According to Psyonix, the core game will not change, and they hope to find a new audience through Epic's launcher. The cost of the sale was not disclosed.
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UPDATE:
After the initial fallout of review bombing and anger from the game's fanbase on Steam, Psionix has edited in a statement on their news post. They've clarified that Rocket League "is and remains available on Steam", and that those on both platforms will be able to look forward to continued support and updates. However, the wording remains unclear if the game will definitively be pulled from Steam one day in the future, only that, for the time being, it will remain on the storefront.
Editor’s Note: We wanted to clarify something for you after today’s news: Rocket League is and remains available on Steam. Anyone who owns Rocket League through Steam can still play it and can look forward to continued support. Thanks!