If you've seen Doctor Strange in the Multiverse of Madness, you'll know that the film revolves around the occultist book, the Darkhold, an item that was first brought to the Marvel Cinematic Universe in WandaVision at the start of 2021. But that very book also plays a very important role in Firaxis' upcoming strategy game Marvel's Midnight Suns, which too has a narrative revolving around the Darkhold.
With this being the case, you may be wondering if there is any crossover or reason for this similarity, and according to the latest edition of PC Gamer magazine (thanks GamesRadar), there wasn't, and the fact that the movie included the book ended up being a "genuine surprise" for Firxais.
It should be said that this does mean that there is "no collaboration" between the game and the movie, and that Firaxis intended to use the Darkhold in Midnight Suns to create a story that was something different to what has been offered up in film and TV in the MCU as of late.