Minecraft

gamedeveloper.com:

Microsoft-owned Mojang is banning the use of blockchain technology and Non-Fungible Tokens (NFTs) inside the Minecraft client and any affiliated server applications. It's a hard stance against the technology that will prevent third-party operators from creating Minecraft NFTs or profiting off of tokens that can grant access to exclusive servers.

In a blog post, the company stated that the use of NFTs violates the spirit of the Minecraft usage guidelines. Since said guidelines do permit server owners to charge for access, it had to clarify why using blockchain-linked tokens as access were not permitted. "We have these rules to ensure that Minecraft remains a community where everyone has access to the same content," the company wrote.

"NFTs...can create models of scarcity and exclusion that conflict with our Guidelines and the spirit of Minecraft."

So not only is blockchain token implementation banned, but any other Minecraft NFTs used for world files or skin packs are banned as well. The company has also banned the practice of allowing players to earn NFTs through activities performed on a server, or earning Minecraft NFTs for activity outside of the game.

"Each of these uses of NFTs and other blockchain technologies creates digital ownership based on scarcity and exclusion, which does not align with Minecraft values of creative inclusion and playing together," the company explained. It added that the use of the technology "creates a scenario of the haves and the have-nots." 

TL;DR:"To ensure that Minecraft players have a safe and inclusive experience, blockchain technologies are not permitted to be integrated inside our Minecraft client and server applications nor may they be utilized to create NFTs associated with any