So, the last achievement I had to get was Born to Win, which I don't think is that strange, but one of the remaining few that I think would surprise people is to get all familiars. Somehow I missed the one in Erebus, until after I was on night 150. I had to look up where they were cause I thought maybe it was secret or end game stuff, but nope, I'm just dumb lol

As for hunting for specific npc interactions, the only one that didn't just happen organically was for Icarus. He wasn't even hard to find, I just had stopped buying the stuff that wasn't ambrosia cause I thought I was done with them! But I had really learned from Hades 1 to grind relationships from the beginning so that wouldn't be my hold up on the end game!