From: Mass Effect series
How many people can say they've risked their lives to save mankind not once, but twice? That's the story with Commander Shepard, who sacrificed her/himself to save the galaxy, only to do it all again when he/she is resurrected by Project Lazarus. Shepard doesn't just care about humanity as a whole, though; behind the galaxy-saving heroics is someone who is deeply empathetic for every member of his/her crew and any person who is willing to battle just as hard as she/he is for the greater good. There's a reason there's so much emphasis placed on getting to know your shipmates beyond just discovering their reach and flexibility; these people are so inspired by Shepard's generosity and drive that they're willing to do exactly what Shepard did: give their lives for the cause. You've got to be doing something right if people are willing to risk that much for your mission.
Whether you play Shepard as renegade or paragon, you're still left with the same fearless resistance, the same desire to take the best course of action, defeat evil, and ensure the galaxy doesn't fade away forever. If Shepard had a code for infinite lives, she/he would give every single one of them to fight the Geth, the Reapers and anyone else who would stand in humanity's way. These are the things that heroes are made of.
From: Bioshock 2
Some bonds are unbreakable; and that's exactly the case for Subject Delta and Eleanor Lamb in BioShock 2. They’re tied together eternally when they are forced to become the original Big Daddy and Little Sister. Their love never dies, not even when their bond is severed by Eleanor’s lunatic mother, Sofia, in an attempt to reclaim her daughter for some twisted higher purpose. Taking on the leader of Rapture, a completely psychotic woman set on some manifest-destiny ideal in an underwater world, Delta is out to set things right in this false utopia. But what sets Delta apart is that he's never really about revenge. He carries only a single thought in his head, and that’s to rescue Eleanor.
While some might argue that Delta is driven by his irresistible, genetically programmed bond with Eleanor, he goes far above the call of duty during his journey. He proves he's not simply in it for himself, ensuring that Eleanor has a shot to live her own life. It's worth the wrath of Sofia and all her fanatical Splicers just to see Eleanor alive and happy. In the end, his bond with Eleanor is broken again, but that does nothing to deter him, and he sacrifices his own life to see Eleanor escape safely.It's strange to think that a bond created so artificially would feel so genuine, but Subject Delta gave Eleanor a life – and depending on your choices, he gave Eleanor a part of himself, too.
How far would you go to save someone you love? If you're Ethan Mars, you're not only willing to give your own life, but also torture yourself to save your son. Mars isn't a superhero, space marine or knight; he's just a father looking for his son. Throughout Heavy Rain, he's pitted against increasingly dangerous trials by the evil Origami Killer, one of the more sadistic villains in games today. Ethan doesn't care about getting shocked by high-voltage wires, driving the wrong way down a busy freeway, cutting off his own finger or (in a totally dramatic, this-is-what-it-all-comes-down-to-moment) drinking deadly poison, so long as it means he’ll get a hint on how to see his son again.
Sometimes, love is stronger than our Darwinian predisposition to stay alive. Putting the life of a single person above your own is the most selfless act we can think of. What would you have done against the Origami killer? It takes an intense amount of willpower to do what Ethan did to prove that love is worth everything, and that when faced with the greatest fear of his life, a man is capable of doing just about anything. As Ethan himself says, "Everything I did, I did for love."