Win and loss conditions

We've implemented our core game mechanics and a simple UI, but Hero Born is still missing an important game design element: its win and loss conditions. These conditions will manage how the player wins or loses the game and execute different code depending on the situation. 

Back in the game document from Chapter 6, Getting Your Hands Dirty with Unity, we set out our win and loss conditions as follows:

• Collecting all items in the level with at least 1 health point remaining to win
• Taking damage from enemies until health points are at 0 to lose

These conditions are going to affect both our UI and game mechanics, but we've already set up GameBehavior to handle this efficiently. Our get and set properties will handle any game-related logic, while OnGUI() will handle changes to the UI when a player wins or loses. 

We're going to implement the win condition logic in this section because we have the pickup system already in place. When...