title: Adding enemy by time interval? and not by coordinate. Html5 canvas game
body: <p>I want to add another enemy. I have this one zombie that pretty much just drops from the sky. Rather than keep adding negative coordinates to drop I'm sure there is a cleaner way to do this?</p>
  <pre><code>new Zombie1({      
        position: {
          x: 4000,
          y: -9500
        },
        velocity: {
          x: -1,
          y: 0
        },
        distance: {
          limit: 7,
          traveled: 0
        }
      }),
  </code></pre>