Tear Jerker / Fahrenheit

• The opening where Lucas is a zombie, and sitting alone being depressed. The whole game from that point is one big How We Got Here.
• The death of Tiffany Harper.
• The death of Jade.
• The death of any of the children in the Wishita Base flashback. Made even worse because, unlike the above two, it is avoidable.
• The "bad" ending, in which most of humanity has frozen to death and the survivors live in sewers praying for a savior.