Here's the data straight from Ubisoft's forum post: Your DLC, luckily, will not factor into the updating process.

If you notice that the download sizes are huge, they are! This update requires the full base game to be redownloaded, so plan accordingly to not unexpectedly fly over your data cap. Not only will your hard drive or SSD have some spare room after the 1.4.1., Valhalla will feature 'faster loading screen times, improved world data streaming, and overall runtime performance' compared to previous versions. A post from the developers on Ubisoft's forums runs down the numbers for each platform, including the update's download size and overall space savings achieved. Xbox Series X is the big winner here, clocking in with a massive 44GB footprint reduction to the game. Title Update 1.4.1 'consolidates the game files, resulting in a smaller overall game size on all platforms,' significantly reducing the space needed to have Valhalla installed. Not content-wise, that's all staying put, but rather the file size of the game will shrink on all platforms thanks to a data restructure.

Assassin's Creed Valhalla is getting quite a bit smaller with a new update next week.

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