Thanks for the Reply. But it said in the bundle that one steam key would be provided. No other game of the bundle included a steam key or mentioned it in the game description.
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In the past, when I found a game like this on a key-seller site, the key from there could be activated on steam. And the games are not visible in the steam store for me.
As long as the game on itch is complete and there are no differences to the steam release, I could buy it here. Steam would be more convienient for me.
Thank you