Steam updates its Season Pass policy to make it clear: no mystery boxes that don't say what the DLC is and when it's coming

"By offering a Season Pass, you are promising future content. In the process of launching a Season Pass you will be asked to commit to a launch timing for each content release in the Season Pass. That launch timing is a commitment to both customers and Steam."

"If you aren't ready to clearly communicate about the content included in each DLC AND when each DLC will be ready for launch, you shouldn't offer a Season Pass on Steam. Selling a Season Pass has risks; since you are promising the release of future content, you have to commit to completing that content on time."

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