It is revealed in that the events of the first game happened roughly 200 years ago, yet Titus remains the protagonist of both. He has a different title in the sequel, suffering a demotion in the ranks of the Ultramarines, yet he doesn't look much older despite the centuries that have past, besides receiving a few more polygons to make him look better than ever. This 200 year gap is brought up casually as well, as if it is normal for Space Marines to live as long as Titus.
With all the factions, decades spent writing lore, and enough books to fill a library, it isn't surprising that there is an explanation for this in 's archives. There's an explanation for almost everything, yet there is a lot of confusion regarding this topic. Although long-lived, it isn't known how old Space Marines can get, nor if they can die in their beds of old age. In a way, Space Marines are similar to the eponymous mutants of, in that they live far longer than the average person, yet always die in battle rather than falling to father time.
Space Marines undergo a myriad of mutations and Gene-Seed implantations to make them the hulking behemoths that tower over ordinary soldiers of the Adeptus Militarum. Gene-Seeds are a catch-all term used to describe the many organs and mutations that are implanted into a Space Marine to make them the feared super soldiers of the Imperium of Man, and these are the key to a Space Marine's long life. Space Marines enjoy such longevity that they don't worry about old age, since they always end up dying in glorious combat with their brothers.
Space Marines in the same chapter refer to each other as brothers. Those in different chapters usually call one another cousins.
Titus himself is actually far older than just 200 years. He was 175 years old during the first game, and it is assumed that he is close to 400 years of age in the sequel, although there is some confusion around the Service Studs on his face. He has four Gold Studs in, which typically represent a
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