Document Type


Lead Author Type

CIS Masters Student


Dr. Yonglei Tao,

Embargo Period



The overall concept of The Defend is to save the Puppies which are in danger from the Puppy monster. The Dog is the hero of the game and the important thing to remember while playing the game is that whenever there is a collision between the dog and puppies, then a chain is formed behind the dog with puppies. Another rule is that whenever there is collision between the dog and puppy monster, there is a decrease of two puppies from the chain. The most challenging part of this development was to detect the collisions, interpreting the User’s touch location on the screen, and implementing various actions to the sprites like sound, enabling movement and most importantly providing the animation.

The Defend is a two dimensional Universal mobile game developed for all IOS platforms. The implementation of this game is done using the SpriteKit framework. To develop a two dimensional IOS game SpriteKit is one of the best available frameworks. The language used for this development is SWIFT. The collisions are detected whenever there is intersection between the frames of different sprites in the game.

As this game is a Universal game, the design of this game is done in such a way that the images are compatible and adjusted automatically with in the screen on any device it is installed. This was implemented with the help of some Auto Layout constraints. This game has been successfully submitted to the Apple App store and has been approved.