[b]"Battered and drained of their Light, these Ghosts are nevertheless valuable for the information they preserve. Their recovered memories may well prove vital to the City's survival. The problem of dead Ghosts troubles the City's scholars. Are new Ghosts still being born? Or is the number of Ghosts dwindling? Will there come a day when no more remain - an end to the rise of new Guardians? If that day is coming, then the City faces a desperate race against time to heal the Traveler before attrition takes its toll."[/b] -- Destiny Grimoire; "Dead Ghosts." We've defeated the Vex God known as the "Black Heart," and the Vex creation known as "Time's Conflux," [b]Atheon[/b], along with the Nexus at the Heart of Venus, and the Undead-Mind at the Heart of the resurrected Black Garden, and more-over we laid siege to the Vault of Glass and neutralized its immediate threat. We've slain the Hive Prince, [b]Crota[/b] and defeated his sisters, [b]Ir anuk[/b] and [b]Ir Halak[/b], and then we went on further, to slay [b]Oryx[/b], the Taken King and his entire Pantheon, from the [b]War Priest[/b] to [b]Golgoroth[/b], and even his nephew, [b]Malok[/b], the Taken Pride of Oryx. We re-captured and then killed the escaped Kell of Kells, [b]Skolas[/b]. We defeated [b]Taniks[/b], and destroyed the Prime Servitor of The House of Wolves, and The House of Devils, [b]Kaliks Prime[/b] and [b]Sepiks Prime[/b], respectively, and after that, we neutralized the Devil Splicers and [b]SIVA[/b], and traversed our way into the War-Mind Bunkers to root out, and destroy [b]Vosik[/b] and [b]Aksis.[/b] And we've slain the most significant Cabal residing in our system, from [b]Valus Ta'ark[/b] to the Shield-Brothers, [b]Valus Tlu'urn[/b] and [b]Valus Mau'ual[/b]... Indeed, through these battles, these Strikes, and Raids, and across the Solar System, from the Cosmodrome to the Prison of Elders, and to the Dreadnaught of the Taken King, we've won victories that the Vanguard will write stories of for generations to come... If they were to survive long enough, that is. But you read correctly Guardians, and there is NO disputing it. We ARE losing this War against the "Darkness," and the reason why is as serious a threat as we've ever fought. Our greatest enemies are not the minions of the Darkness... Our greatest enemy; our greatest threat is a two-headed monster, and its names are, [b]"Time"[/b] and [b]"Attrition."[/b] We're fighting a War against enemies whose numbers are vastly innumerable in comparison to our own. For every one we slay, another horde rises to replace the one slain. The number of Hive, Taken, Fallen, Cabal and Vex slain in Destiny numbers well over the Tens-of-Millions, into the Hundreds of Millions, and even "Billions." But they don't stop coming... And we Guardians, though we are a force to be reckoned with... We're not indestructible, and we are not perfect. [b]"Thanks to their Ghosts, Guardians are effectively immortal in most situations. They take advantage of this fact in a number of ways, whether it’s the live-fire training exercises of the Crucible, or by making new discoveries via visions as thanatonauts. However, Guardians can be permanently killed if their light is drained by a powerful enemy, or if their Ghost is destroyed."[/b] -- Destinypedia. Every one of us has experienced "Death." From a simple fall off a ledge, to being swarmed by overwhelming numbers of enemies, to being stomped by the more massive ones, and most times, our Ghosts have revived us and restored our Light. But there are ways to kill a Guardian... And it has been done in several, significant cases, documented in the Grimoire of Destiny. [i]Dredgen Yor[/i] was banned from the Crucible, and exiled from The Last City, because the use of his Thorn; the original Thorn, would drain a Guardians Light beyond the ability of their Ghost to revive them. The Description for the Red Death pulse-rifle reads: [b]"Vanguard policy urges Guardians to destroy this weapon on sight. It is a Guardian killer."[/b] -- Destiny Grimoire; Red Death. Presumably, the Red Deaths original design was somehow used to draw from the Light of other Guardians, using it to heal the wounds of its wielder, but at the detriment of its victims. I believe that after multiple instances of losing one’s light to the Red Death, it would bear an effect similar to the effects of Thorn; Draining a Guardian's light to the point that they would be unrevivable by their Ghost. In particular, outside of the Weapons said to be Guardian Killers, there was once a Period in which Guardians would actively War against, and execute one another, as described in the Lore of Destiny: [b]"Outside the Last City, various Guardians also set themselves up as petty kings across the Earth. Known as Warlords, they forced villages to accept their "protection" in return for tribute, and warred with each other for territory. Eventually, four warriors who fought against the Warlords' tyranny, [i]Radegast, Jolder, Perun,[/i] and [i]Saladin,[/i] joined together to form a force for good modeled after the knightly orders of old. They became the first Iron Lords. Over the years, the Iron Lords' numbers swelled into the hundreds as they defeated Warlord after Warlord and destroyed their Ghosts to ensure their executions were permanent."[/b] -- Destinypedia. This, more than anything else, should offer proof that the numbers of the Guardians are dwindling. It's a slow, steady rate of decay, but it is decay, none the less. From The Faction Wars and the Iron Lords execution of various "Guardian Warlords," to the battle of the Twilight Gap to the event known as "The Great Disaster." While many are familiar with some of the Lore regarding "Battle of the Twilight Gap," there is, on the other hand, little knowledge in-game of, "The Great Disaster," apart from our Ghosts passively mentioning, 'We gave up the Moon to keep The Hive away from Earth; we hoped that would be enough for them." For those who don't know what, "The Great Disaster," is, allow me to give you a brief explanation, courtesy of "Destinypedia.com." It reads: [b]"Shortly after discovering the Hive during the battle of Burning Lake, the Vanguard ordered a full-scale assault on the Moon to establish a beachhead. [i]Lord Shaxx[/i], however, warned the Consensus that the Ascendant Swords carried by the Hive Knights were unlike any weapon he'd seen before, and that they should delay the attack. His pleas were ignored, and the Guardians who arrived fell by the hundreds, as leading the Hive army was the God-Prince Crota, an invincible Knight who devoured the Light of the Guardians. Mare Imbrium was one of the battlefields, as Crota led one thousand Knights against over five hundred Guardians, easily cutting through them. It was claimed the sky above the region, 'turned into green fire.' During this campaign, an unknown Titan created the first Thunderlord, along with two other machine guns that came to renown. Though the Thunderlord survived, its counterparts were lost. In the aftermath, the Vanguard classified the Moon as forbidden, and not to be visited unless absolutely-necessary. One of the survivors of the battle, [i]Eriana-3[/i], swore revenge against Crota and assembled a team of Guardians to enter the Hellmouth alone. Only [i]Eris Morn[/i] survived that venture."[/b] As you can see from just this battle itself, Guardians have, Historically, suffered immense casualties when we've faced Large-Scale battles, and though our "Main Character" stories have seen us survive every significant conflict we've faced, we've been given no true insight to the casualties that may have been sustained at the Taken Invasion, or from the awakening of [b]SIVA[/b] by the Devil Splicers. The unsettling likelihood is that we did not come away from these most-recent conflicts unscathed... The very-real-truth, Guardians, is that no matter how many enemies we've defeated, they continue to come... And over the course of centuries, and even recent decades and years, our own numbers have begun to shrink... And for all of the "Dead Ghosts" we discover, we have no assurance, no guarantee, that new Ghosts are being created to take their place; and if there is no evidence that new Ghosts are being born, the most likely reason is because there aren't new Ghosts being born... And if there are no new Ghosts, that means that there is only one, frightening truth. We're battling the Darkness on "borrowed time." And time only does one thing, Guardians. [b]It ticks away.[/b]