Tear Jerker / Surviving Mars

• The first time one of your colonists dies. This person left their home behind to help advance humanity and is eulogized as a hero, but in all likelihood this person spent the rest of their life in one dome with 12-13 neighbors and will never get to see the fruits of their efforts.
• Having a dome suffer a failure in it's life-support system, causing everyone inside to die painfully. It's especially tragic if you have no way of saving them in time, as you're forced to helplessly watch them perish.
• Population Control can be this if you look at it from the point of view of a colonist. Somebody desperately wants to be a parent but is told they will never be allowed to because of the dome they were assigned to live in. Eventually they become too old to become a parent and are left wondering at what could have been. You can always build more housing and more domes to accomodate the new colonists, but the population will keep growing anyway and reach those limits again (and you can't do that ad infinitum, each extra dome requires oxygen, water, electricity, food and maintenance). And the game offers no other viable alternative to deal with overpopulation. You can't send your colonists to found new Mars colonies, or to join rival colonies, or to man structures elsewhere, or to colonize other planets, and you can't even let them return to Earth.
• The Grip of the Lawless event becomes this if you choose the option to execute the renegade. It's clear that the colony commander's idealistic dream died this day.
  "So it has come to this - our first executions on another world. Humanity will never change."
• One of the options for the Holy Dome event reads as this if you are religious. The mission commander tries to enforce his own atheism, and in doing so costs utterly alienates his religious colonists - their comfort drops to 0, which will surely sink their morale and cause any Earthborn religious colonists to leave if they're so unwelcome. How many of them worked, for the good of the colony, perhaps for years, only to get this slap in the face.
  "This is absurd! Religion has no place on Mars."