Hello, I really would like to buy Cyberpunk 2077 on GoG!
But then I have a question.
Will I be able to see it in my Steam and Epic Games collections like it was with some other games that were activated by access keys?
Will I be able to run the game from those other environments as well?

No. If you buy the game on GOG you will receive it DRM free, meaning you can start either from the GOG Galaxy Client or just from the .exe file. EDIT: Like others mentioned you can add it as a non-Steam game, but this will only function as another client to start it and your achievements will be handled by GOG.

If you buy it on either Steam or Epic, you can add those accounts to Galaxy so you can start it from within the Galaxy Client. But not the other way around.

Regional pricing ...
Thats why i may get it on steam 42 us dollars converting to turkish lira is : 324.79 lira. on steam it is 249.00 lira . a major price difference.

On Steam you can "Add a Non-Steam game" and link the executable, the game will pop-up in your library and you will be able to launch it from Steam but the page of the game in your library will be empty.

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The fact that the price isn't the same is a good point. But at the same time, what you're purchasing isn't the same, either.

In one case you're paying only for temporary, revocable permission to play the game, which is attached to a specific DRM system (Steam), while in the other case you are paying for the right to possess a copy of the game, independent from any DRM system.

In general, if you don't think a game is going to be worth a certain amount of money, I would just wait until the price reaches the level you find acceptable.

But having said that--I don't know about the options in your region, but I specifically wanted the box (that comes with everything but a copy of the game :P), and I was very surprised to find that it was actually ~$10 USD less than the downloaded ("digital") version at the retailer I used.

Yes, you can add them as a ''non-steam game''. But all the achievements are handled on GOG and not steam or epic.

I'd guess, if you're buying from GOG - you just might want to get your downloaders/installer via GOG website via a web browser; or just use GOG Galaxy to handle download and updates.

Then - you can add CP 2077 as a Non-Steam game via Steam, if you want to run a Non-Steam version of a game (like GOG's version) through Steam.