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Learning XNA 4.0 by Aaron Reed

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Adding Biohazard Bombs of Insanity!

Let’s modify this game to make things a little more interesting. Rather than just having one player chase another player around the screen, we’ll let the chased player drop biohazard bombs every 5 seconds, which will cut the movement speed of the chasing sprite by 50% for 5 seconds. That should spice things up a bit.

First, you’ll need to add a few more resources. Add the hazardhit.wav and hazardplant.wav files to your CatchContent\Audio folder in Visual Studio (the files are located with the source code for this chapter in the Catch\CatchContent\Audio folder), and then add the hazard.png image to your project’s CatchContent\Images folder (that file is located with the source code for this chapter in the Catch\CatchContent\Images folder).

Next, you’re going to need to send two new message types between the two computers, for when the chased sprite plants a bomb and when the chasing sprite hits a bomb. Add two new message types to the MessageTypes enum:

// Represents different types of network messages
public enum MessageType { StartGame, EndGame, RestartGame,
    RejoinLobby, UpdatePlayerPos, DropBomb, ChaserHitBomb }

Next, add the following class-level variables to the Game1 class:

// Bomb variables
int bombCooldown = 0;
List<UserControlledSprite> bombList = new List<UserControlledSprite>(  );
int bombEffectCooldown = 0;

The bombCooldown will be a cooldown timer indicating when the next bomb can be planted. The bombList is a list of bomb objects. The

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