Dominic Santiago is the first face players see upon starting the campaign for the original Gears of War.

It's Dom who breaks Marcus out of prison and throws him headfirst back into the war against the Locust. He begins the saga, and in many ways, he ends it.

While Marcus is the "main character" of Epic's Gears of War trilogy by default, it is Dom who propels the trilogy's story forward. Dom, not Marcus, is the real heart of Gears of War, because he's the one character players are allowed to form an emotional connection with.

Marcus is the "cog in the machine," the grizzled soldier of few words who saves the day. He's largely emotionless. But Dom is something more, and serves as the entire backbone upon which Gears of War exists. The franchise may have begun as a brotastic, man vs. monster story, but it would be Dom that proved Gears of War could also be something more.

That wouldn't become entirely clear until later in the trilogy. In the original Gears of War, Dom is a friendly, logical and loyal friend to Marcus. While fellow Delta squad members Augustus Cole and Damon Baird prove to be bombastic and sarcastic respectively, it is Dom who is the most grounded and relatable of the bunch. It is Dom who makes the decision to use his connections with the Stranded, a group of people deeply disliked and distrusted by his fellow squad members, to ensure the success of Delta Squad's mission. He's practical, capable and with Marcus through all the ups and downs.

It wouldn't be until Gears of War 2 that Dom, Marcus' "sidekick" in the first game, became the franchise's most important character. Though hints about Dom's missing wife Maria came in the original Gears of War, it is in the sequel that Dom's quest to find her takes center stage. During what is practically a suicide mission into the Locust stronghold known as "The Hollow," Dom and Marcus discover pods of human prisoners, leading Dom to desperately search for his long-lost lover within them.

And find her he did. In one of the franchise's most emotional moments, Dom finds his Maria, and is at first blind to the reality of what is before him. Upon releasing her from her containment pod, he can only think of the beautiful woman he loves as he remembers her from all those years ago. They share a passionate embrace. It's only after Marcus brings Dom back to reality that he sees the truth.

It's never really explained what exactly the Locust did to Maria (or why), but it's clear that she is both physically and mentally broken from torture. She fails to recognize Dom, can barely stand and is little more than a husk of a human being. Marcus, always the man of few words, simply tells Dom it will be okay and walks off, leaving Dom to put Maria out of her misery.

In one single, 3-minute cutscene, Gears of War changed. There are, of course, plenty of shortcomings in how Gears of War decides to treat Dom's wife. She isn't a real character in any sense, her death exists solely to move Dom's story forward and there's of course the controversial issue of Dom essentially euthanizing her. Marcus later tells Dom that "he did what he had to do," but maybe there was some way Maria could have recovered? Maybe that's wishful thinking, but the game chooses not to explore the option.

How Maria's death is handled in Gears of War 2 wouldn't work in some games, but it does work for Gears of War, largely because few players were expecting such a traumatic and emotional event. After all, Gears of War is perceived by those both familiar and unfamiliar with the series as being about four muscular space marines fighting monsters with chainsaw guns. It's not exactly high art. But Maria's death and the lasting effect it has on Dom changes what the series is about. No longer is it about fighting to survive or winning a war against monsters. It becomes about loss.

By Gears of War 3, humanity has, in fact, lost. The Locust and the mutated Lambent they had been fleeing from for decades dominate the Earth, with humanity struggling to get by in hidden settlements or aboard massive aircraft carriers in the middle of the ocean. Everybody has lost somebody or something, but none more so than Dom. A cinematic and somber advertisement for the game clearly shows Dom has little reason to continue fighting, nearly letting himself be killed by a Locust drone before Marcus steps in to save him.

Dom is only living for Marcus. Though Dom has long given up on his own happiness, he stands by his friend, loyal to the end. When their mission brings Dom, Marcus and the rest of their squad to Maria's hometown of Mercy, it gives Dom yet another reason to reflect on what he's lost. Speaking at the grave of Maria's family, he tells Maria Marcus "is busy saving the world again" and that he has to be there for him.

So when the lives of Marcus and the rest of his friends hang in the balance a short while later, Dom knows what he has to do. In the emotional crescendo of the entire trilogy, Dom drives a truck into a fueling station at full speed, causing a massive explosion that annihilates all the Lambent forces descending upon Marcus and his squad, saving their lives in the process.

That the developers chose to use the now-iconic "Mad World" track during the scene, made more famous by an advertisement for the original Gears of War, is fitting. Though the version of the song used during Dom's death scene doesn't contain lyrics, anybody who's heard the song can easily recite the words. The phrase "dreams in which I'm dying are the best I've ever had" seems especially relevant to what's happening on screen, as Dom shouts to the heavens "Never thought it would end like this, huh? Huh Maria?!" before exploding in a ball of fire as Marcus, horrified, looks on.

It's also fitting that the trilogy's finale circles back to Dom. As Marcus and Delta squad eventually complete their quest to destroy the Lambent and the Locust in one fell swoop with a powerful (and convenient) superweapon, Marcus is confronted by the wounded and spiteful Locust queen, Myrrah. Marcus promptly stabs her with a knife given to him by Dom, telling her the pain she feels is from Dom and all the others she killed.

Never mind that Myrrah didn't actually kill Dom. Nor did her Locust forces. But it was her and her army that caused Dom to lose so much. In many ways, Dom was dead long before he decided to crash that truck into the fueling station, and I think Marcus realizes that as he speaks the last words Myrrah will ever hear.

Later, as Marcus sits with Anya on a beach, he wonders what it all was for. The death of Dom. The death of his father. The death of countless friends over the years. What, really, did their struggle for survival achieve? What did so much loss bring them? "What's left?" he asks. "Tomorrow, Marcus," is Anya's reply. "We've finally got a tomorrow." That tomorrow was only possible thanks to Dom, a man who felt like he had no tomorrow of his own.

Dom is the heart and soul of Gears of War. In a franchise about struggling to find hope after losing so much, about continuing to fight even after there's almost nothing left, Dom serves as the emotional anchor by which players connect. Without Dom's story line, Gears of War would have been an entertaining, but emotionally flat cover-based-shooter. With Dom, Gears of War became something more.

With the release of Gears of War 4, the saga of Marcus Fenix will continue without Dom, but it's clear that developer The Coalition is aware of just how important Dom is to the series. In a way, Dom lives on in Gears of War 4's protagonist J.D. Fenix, Marcus's son. I'll let you guess what the "D" in his name stands for.