In the Wiki it says:
You can continue building your empire, until your MC dies of old age
So far I've been playing this game for 3 weeks, and I'm nearly 6 months in. My MC is 30, and I just realised he could live to be at least 150, or maybe a lot more (one character claiming that some Spheremasters live for centuries). So at least another 120 years, which at the present rate of progress would take me 18-20 years. No doubt I'll run out of new quests long before that, and probably things will speed up? But even so, I don't see me reaching the MC's demise from old age, anytime soon.
If he takes 'Revitalise' couldn't he technically go on living indefinitely? So the game might never end, and I might end up dying of old age before the MC?