Need help creating giveaway

Create a giveaway for one of the games that key activates. As long as the winner gets the game advertised in the giveaway, it's fine if they receive bonus contents.

Medieval II: Total War Collection (just type that in)?

There are entries for the whole collection isn't it, and each game/collection has it's own seperate key?

TempeteJoachim gave you the only valid answer you're going to get. Since that particular combination of games isn't sold on the Steam store, it's not part of the Steamgifts database.

Best thing to do is pick the game that people are most likely not to own already. I would probably go with Medieval II: Total War Collection since owning the base game would not prevent someone from entering for the rest.

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