public CircleSpawn(EnemyDifficultyEntry enemyDifficultyEntry, float radius = 1f, int amount = 4, float modifier = 1f)
 {
     this.enemyDifficultyEntry = enemyDifficultyEntry;
     this.radius   = radius;
     this.amount   = amount;
     this.modifier = modifier;
 }
 public SingleSpawn(EnemyDifficultyEntry enemyDifficultyEntry)
 {
     this.enemyDifficultyEntry = enemyDifficultyEntry;
 }