refactoring

Scripts/Elements/Liquid.cs

@@ -17,7 +17,7 @@ public abstract class Liquid : Element {
         return true; // not necessarily end, subclasses could do some more things
     }
 
-    protected override void Tick() {
+    protected virtual void Tick() {
         Vector2I randomDirection = RandomDirectionDown();
         if (randomDirection.Y != 0)
             randomDirection *= Vector2I.Left * (int)(GD.Randi() % MAX_VERTICAL_SPREAD);