Im working on a simple game for windows phone. There is one item in the game where the player can click on a enemy and shoot him. Well there is a 1:2 chance for the user to shoot the enemy and when he fails I want to tell this to the user. A Popup would stop the gameflow so I don't really want that. What are other possible ways to do that ? It doesn't need to be a lot of text just "Miss !" or "You missed !".
You are probably not looking to use a system notification (like a toast), but rather using some type of in-game notification.
For something that simple and self-contained, I would suggest just having the text appear in red (you might want to fade in and out) somewhere on the screen. That way, the user will get the necessary information without being completely distracted.
I would suggest, exactly as you said, simple text. Take the word "Miss" and have it in red, just have it pop up next to the enemy quickly for a moment, animate it to allow the user to see it and have it quickly move out of the way. That way they don't lose attention on the enemy but they know what happened.