This game is from HB. In HB, its name is: "Alien Colonial Marines Collection". I cannot determine whether this key refers to the app ID (collection) or the sub ID (bundle). But I think it does not matter. You can enter this giveaway either for the base game or the DLCs.

1. Game from Humble Bundle.
2. Will not check multiple wins / unredeemed keys for other games.
3. Will check the ownership / winning history of this game manually. A reroll request when the rule is broken.