you want me to spoil more for you? well master chief(john) and that doctor person have a choice to make at the end on how to destroy the invading covenent. master chief decides that the only way to save humankind is to jump into the reactor and destroy it himself, which undoubtedly ends his life.....probably the best ending of any game i've ever played. MASTER CHIEF WILL FOREVER BE MEMORALIZED!!! Bungie was effin brilliant in how he will now be looked upon as the greatest game character ever!!! BEST GAME EVER!!!