[X] The Sword That (Actually) Ends The World
The Hero never gave up. For all of his friends that the Tyrant killed, he never gave up. For all the sacrifices he made, he never gave up. Through that brutal, decade-long slog of a war, the Hero remained determined. To give up now, when he was just told that there was a power behind the Tyrant, orchestrating the ruination of this world? I refuse to make that choice. Through pain, through heartache, through war and strife, the Hero has fought to save everyone he could. The power offered by Progression+Praxis will allow him to save an infinite multitude more.
I imagine the Hero would not enjoy the effects of Decimation, but could reasonably decide to pick it. After all, he has seen a world in which evil nearly won, where the best and brightest were cut down in their prime, where the noblest of souls were snuffed out in an instant. Compared to the Hero lacking the ability to defeat a Tyrant, what is the worth of a few years of life? Practically nothing. After all, how many people died in that gruesome war against the Tyrant? How many countries were ripped apart at the seams? Is preventing something like that from happening again worth lowering the average life expectancy a few years while the Hero saves the world? It is most certainly a Curse that taints any victory with the sting of everyone dying a little earlier, a Devil's Bargain that exchanges life for power, a "kill one person to save ten others" decision... but that's exactly what the Hero would choose. Because the Hero has born witness to what happens when you do not grasp at every ounce of power available to you: Kingdoms fall, loved ones die, and evil reigns supreme. To that end, a Curse that does not inhibit his capabilities and only exacts a small toll from those he's defending... isn't it the best option he's got to smite whatever evil threatens those he would protect?
And the Doom of the Tyrant... well, what has authority done for him, exactly? The Tyrant slaughtered all the Hero's loved ones, leaving him a broken husk. And when the day was saved and evil was no more, when the Hero turned towards the Kings and Rulers for assistance in making the world a better place, what did they do? They turned their backs on the Hero, spurned his ideals, content to live as petty tyrants over kingdoms of stagnation. No, there is no love found in the Hero for rulers or leaders. If he wants something done right, he'll have to do it himself.
And as for the Praxis, could there truly be any other choice? A style that utterly rejects any individual's talent, relying solely on effort and self-sacrifice? For a Hero who found he could not rely on his talents when it mattered most, who found the only real gift he had was the will to sacrifice what was needed on the alter of power? A dream of fairness, defiant against the uncaring universe? Just as the Hero had dreamed of real, true democracy for his world, only to be spurned by uncaring monarchs? No. There can be no other choice than this.
Also, for those arguing that Freedom should be chosen, that the Hero could simply live free of any higher destiny or ambition, that is false. This is the Rihakuverse, and any ideas of "Freedom" or "Safety" are mere illusions to be discarded in the search for ever more accumulating power. There will always be a bigger fish, a man behind the man, a secret hidden boss that is capable of wiping out your comfy domestic life in an instant. Whether it be a cultivator consuming your universe for power, or a clash between Gods that scatter multiverses like grains of sand, or even an alien Tyrant deciding that they would like to have what is yours, there is no safety here. The only security possible is outscaling all those who oppose you, rendering every being that would threaten you harmless, accumulating more and more and more and more and more in a mad dash to keep that which is most precious safe.
Peace is a lie, there is only sheer, unrelenting power, enough to wipe out all evil that opposes you.