Why is Season 3 dusk so much younger looking than Season 1?

So, in the first episode of season 3, the then-Dusk is about to ascend, and he doesn't look much older than any of the other Dusks in the show. But in, i think the 3rd episode of season 1, we see an ascension for the first time, and that version of Dusk looked much older. If they're both the same age when they ascend, why do they look different?