According to Venturebeat, playing an hours worth of the Splatoon 2 Testfire, the game only took up around 150mb worth of data using T-Mobile LTE. They make note in saying the game played fine and their experience wasn’t impacted while playing on a hotspot. So if you have the ability to do this and have a bunch of unused data, you can play Splatoon 2 anywhere you go!
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