diff --git a/Shared/ShmupWorld.cs b/Shared/ShmupWorld.cs
index e0b129e..eba64f2 100644
--- a/Shared/ShmupWorld.cs
+++ b/Shared/ShmupWorld.cs
@@ -14,10 +14,9 @@ namespace SemiColinGames {
 
       private float speed = 150f;
       private float shotCooldown = 0f;
-      private ProfilingList<Shot> shots = new ProfilingList<Shot>(10, "playerShots");
 
-      public ProfilingList<Shot> Update(
-          float modelTime, History<Input> input, Rectangle worldBounds) {
+      public void Update(float modelTime, History<Input> input, Rectangle worldBounds,
+          ProfilingList<Shot> newShots) {
         // Movement update.
         Vector2 motion = Vector2.Multiply(input[0].Motion, modelTime * speed);
         Position = Vector2.Add(Position, motion);
@@ -28,14 +27,12 @@ namespace SemiColinGames {
 
         // Check whether we need to add new shots.
         shotCooldown -= modelTime;
-        shots.Clear();
         if (input[0].Attack && shotCooldown <= 0) {
           shotCooldown = 0.2f;
           Vector2 shotOffset = new Vector2(12, 2);
           Vector2 shotPosition = Vector2.Add(Position, shotOffset);
-          shots.Add(new Shot(shotPosition, new Vector2(300, 0)));
+          newShots.Add(new Shot(shotPosition, new Vector2(300, 0)));
         }
-        return shots;
       }
 
       public void Draw(SpriteBatch spriteBatch) {
@@ -108,6 +105,7 @@ namespace SemiColinGames {
     public readonly ShmupPlayer Player;
     public readonly ProfilingList<Enemy> Enemies;
     public readonly ProfilingList<Shot> Shots;
+    private ProfilingList<Shot> newShots;
 
     public ShmupWorld() {
       Bounds = new Rectangle(0, 0, 1920 / 4, 1080 / 4);
@@ -115,6 +113,7 @@ namespace SemiColinGames {
       Enemies = new ProfilingList<Enemy>(100, "enemies");
       Enemies.Add(new Enemy());
       Shots = new ProfilingList<Shot>(100, "shots");
+      newShots = new ProfilingList<Shot>(100, "newShots");
     }
 
     ~ShmupWorld() {
@@ -127,7 +126,8 @@ namespace SemiColinGames {
 
     public void Update(float modelTime, History<Input> input) {
       // Update player, enemies, & shots.
-      ProfilingList<Shot> newPlayerShots = Player.Update(modelTime, input, Bounds);
+      newShots.Clear();
+      Player.Update(modelTime, input, Bounds, newShots);
       foreach (Enemy enemy in Enemies) {
         enemy.Update(modelTime);
       }
@@ -136,7 +136,7 @@ namespace SemiColinGames {
       }
 
       // Add new shots.
-      Shots.AddRange(newPlayerShots);
+      Shots.AddRange(newShots);
 
       // Reap off-screen objects.
       Rectangle paddedBounds = Bounds;