Enty Lawyer, the author of the blog "Crazy Days & Nights", published a post on November 30th last year implying that Activision-Blizzard used an exploit built into the microtransaction engine for Hearthstone to rig a tournament for [Chinese player VKLiooon](https://archive.is/AiByY). >>This A list gaming company which is a merger of two big companies has a patent in which their match making services (traditionally random based on certain parameters) can be rigged in order to influence in game purchases. If one reads between the lines, this implies that all random events in their games are determined server side. >>The ramifications of said patent were present for all to see at the online collectible card game world championship in 2019. In said tournament, the company fully rigged random results left and right in order to obtain political favor with China. This incident occurred within a few weeks after the company banned multiple players for speaking out against Chinese oppression of Hong Kong. >>Examples of rigged events on behalf of the Chinese player included always having certain key cards in her hand by X turn, always going second when playing a deck that greatly benefits from going second, or random results from cards played always swinging significantly in her favor. The basic idea is that the matchmaking in Hearthstone is driven by the microtransaction engine. When you make purchases, the system will steer you towards matches that will make the most use out of them. By manipulating this system, players can be matched up in such a way as to maximize the effectiveness of their decks against any given opponent. I haven't read the patent myself, so I can't verify any of this. Take it with a grain of salt, but it wouldn't surprise me in the least given how desperate companies are to break into the Chinese market. Source: [Blog post (archived)](https://archive.is/jB1nS)