So, after not playing for almost a year, I decided to try out Master Mode.
My goal was to play enough that I could be strong enough to beat the game, without doing any of the divine beasts.
It was a lot of fun. Exploring around to randomly find shrines felt mostly new, as I didn't remember where most shrines were. The beginning is super tough; you basically just have to avoid all enemy encounters, as you won't be able to defeat most enemies before you break every weapon you have.
I eventually got enough shrines to get the master sword (trading in the couple stamina upgrades I'd gotten to get it sooner). With the Master Sword, I was able to defeat most enemies, though I still died a fair amount of the time. Upgrading armor seemed to help a lot.
So once I got 16 hearts and a couple stamina upgrades (64 shrines done), I headed to Hyrule Castle. Got the Hylian Shield. The Ganon fight is insanely difficult. Having to go through all 4 bosses wasn't too bad, though it used up several of my healing items.
The second half of the first phase of Ganon is where it gets crazy. He will be invincible most of the time; you can only damage him when he does something that you can counter. (Either parry a beam, or flurry rush a sword strike). This lets you do a bit of damage before he goes invincible again. The problem is, in Master Mode, he heals while you aren't doing him damage. And he's invincible, so he's going to heal every time. You need a combination of luck, hoping that he attacks quickly enough that he hasn't healed too much yet, and perfect play, because if you miss a single counter, then he will almost always be fully healed before you can touch him again.
The first time I did this fight, I spent over an hour fighting him. Him constantly healing back to full (technically back to half, where he is when he enters the second part), and me constantly healing back to full thanks to having lots of food. But he won the war of attrition; eventually I used up all of my hundreds of healing items. And eventually my Hylian Shield broke, at which point it becomes just a waiting game until you die. I was using damage+ items as well, but they ran out too quickly.
The second time, I prepared more... got several fairies, several more full-heal items, several more damage+ items. And upgraded my armor more. I over-prepared though; I eventually beat him with a fair number of healing items, attack+ items, and fairies left. The final phase is just as easy in Master Mode as it is normally. Still fun though.
The last thing I want to do before I call it quits again is to get enemies upgraded to the new Gold level. I finally found some Gold Lizalfos... they did not disappoint. Aside from just being Gold, they seem to increase their numbers as well. The camp I found had 2 Black, 2 Silver, and 2 Gold Lizalfos. Even though I had multiple fairies going into it, I died 4-5 times before I finally defeated them all. I'll keep killing more random enemies until I see Gold of all 4 types (including the Gold Lynel), and then I'll be done.