匿名协同程序

首先,我想做的是:

delegate IEnumerator EnemySpawningRoutine();

EnemySpawningRoutine[] enemySpawners = new EnemySpawningRoutine[] {
    () => {
        //variables
        //spawn
        yield return new WaitForSeconds(3f);
        //complex stuff
        //more spawning
    },
    () => {
        //same as above
    }
};

IEnumerator EnemySpawningRoutine() {
    IEnumerator currentSpawnRoutine;
    while(isGameRunning) {
        currentSpawnRoutine = //choose one of enemySpawners
        StartCoroutine(currentSpawnRoutine);
        yield return new WaitUntil(() => {
            //return true if all enemies are dead or something like that.
        });
    }
}

不幸的是,这似乎是不可能的,因为委托或匿名函数不支持yield-return功能。

有没有其他方法可以在不使用匿名IEnumerator的情况下达到上述效果?