the thing is, Zenos was a false start, he is someone that should not be, he is a wrongness. this he knows, it is all he knows, he is an uncanny-valley prototype of a fully realised individual and he should not be. he does not want to be alive the way that he is; his strongest desire is to die -- no, not merely to die, to be killed. without any framework to convince him otherwise, he thinks this is a simple and straightforward desire, a perverse sort of suicidality, the perverseness of it a mere quirk of being a Galvus (they've always been a little off, haven't they? the royal madness is well-known, accepted as simply the heaviness of the crown).
but the context he is missing is that his desire is not merely to be killed, but to be cracked open. to be freed. he sees and feels in greyscale, the vibrance of the world and the mortal experience unknown to him except in the moments when he is closest to death. the redness of his blood brings the world into sharp focus, brings a blooming feeling to his gut, brings a rich and exultant feeling to his spirit. he is alive, then, at the hour of his death.
this feeling is unknown to him except in the moments when he is closest to death... and when he sees Dayir for the first time.
at that fateful meeting in Rhalgr's Reach, he feels something crack in his core, and it feels like a bone break but it's deeper than that. he knows he has met the person who will kill him. she who is clothed in the Sun, she who would pierce him and fill the wound with Light. and from then on, that is all he cares about -- the when, the where, and the how.
when the hour finally comes, Dayir is well-practiced at bringing death. she has brought death to those who needed that divine rest the most -- the Unsundered, trapped on their wheel -- and she is now bringing this sweet embrace to a thing that should not be. and Zenos knows: this is the hour. he, too, a thing that should not be, will be released from his bondage.
and after Endsinger's defeat, Dayir finally gives him what he wants. she pierces him and fills him with Light. and the death he sought at the Royal Menagerie is finally complete, and it's strange, how beautiful it is here at the edge of all things, here, at the hour of his awakening.
to be killed, to be cracked open, to be freed. the wrongness is righted. the rest of his soul floods in through the wound, the vitality he'd been denied. the first day of Zenos's true life, by the will of the Star, by the hand of one who knew him and loved him, entire.