Majora's Mask. Took what OoT did and built on it. The Groundhog day elements were brilliant, it felt like the world around you was alive, rather than a bunch of bots spawning in, stumbling their way about with inadequate path-finding before disappearing round a corner and de-spawning. I couldn't count the amount of time I spent trying to work out how to make a perfect 72hours in Termina. Unfortunately, I never did manage it. Someone always had to do without. (Probably the guy on the toilet, the letter was too important to be used for your purposes, I hope you found another way to well you know...)