AC Odyssey was the first one in the entire series I couldn't push myself to finish. I used to love just bumping around eliminating every single map icon, but Odyssey was way, way too big, and having my zen ruined by bounty hunters all the time was exhausting.
I heard Valhalla was even worse. It was the first one I skipped after playing each one since the original (even some of the 2D ones).