Not complete game, specifically says so in game – Age of Defenders - Multiplayer Tower Defense and Offense post apocalyptic RTS HD Review

You must register with their service (Geewa) to get access to "full single player campaign and multiplayer". There is no excuse for this and Apple should ban this publisher for the misdirection, especially for a game that is not free. I agree with other reviewers who state that the game gets to a point where you must spend cash on IAPs to proceed as well.
Review by Cracatoa on Age of Defenders - Multiplayer Tower Defense and Offense post apocalyptic RTS HD.