Buy Assassin's Creed 5 Unity

For Steam CD Keys, you must download (HERE), install the Steam software and create a new account. If you already have a Steam account, once you log in, click "Add a game" (located in the bottom left corner), and then "Activate a Product on Steam". After a few more clicks, you will be prompted to type in your game code. Thus, the game will be activated and automatically added to your account library.

Use your code on the Xbox Live network to activate your games or increase your Xbox Live account's credit. To access the Xbox Live network, you need the Xbox One, a broadband connexion, a Xbox Live account, and a storage device according to your console: Hard disk drive, memory card, or USB drive.

Uplay is Ubisoft's Download Platform. If you still don't have the client, you can download it HERE, install it, and create a Uplay account if you don't have one already. Then you will have to get the Download Manager related to your game, unzip its content and use the .exe file which will download your game. At last, once the download is over, you just have to get back on Uplay where you will see your games cover and click it to activate your CDKey.

You need to use your your game CD Key on the Playstation Network to download your game. To access the Playstation Network, you need a Playstation 4, a broadband connexion, a PSN account, and a storage device according to your console: Hard disk drive, memory card, or USB drive.
Playstation Plus Subscriptions are compatible with PS4, PS3 and PS VITA.

This is the Epic Games launcher. You must download the client HERE, install it, and then create your account. When you sign in to your account, click on your avatar and then on "Redeem Code". Enter your Key, your game will automatically be added to your library, and the download will start.