20150704_GameOver.cs

using System;
using System.Collections;
using UnityEngine;
using UniRx;
using UniRx.Triggers;

public class GameOver : MonoBehaviour {

    void Start () {
        // プレイヤーが触れたらリトライさせる
        this.OnTriggerEnter2DAsObservable()
            .Where(x => x.gameObject.tag == "Player")
            .Subscribe(x => {
                Application.LoadLevel("main");
            });
    }
}