public Entity Retrieve(Queue<Entity> pool, string[] prefabs, string tag)
{
Entity entity;
if (pool.Count > 0)
{
entity = pool.Dequeue();
}
else
{
var prefab = prefabs[WaveServices.Random.Next(prefabs.Length)];
entity = this.EntityManager.Instantiate(prefab);
entity.Tag = tag;
}
return entity;
}