One year and three months after starting it, shu3 just recently completed an absolute monster of a completionist challenge playthrough of Breath of the Wild, the BotW (Superchallenge That Went Beyond All Others BotW) run.
Apart from the normal challenge rules like 3 hearts, he's also got a bunch of other fun rules, like the only weapons and shields he's allowed to use are household items, or all photographs must be selfies. It's also a lore explanation run, and he prepared for it by first playing through all other Zelda games, and he explains the lore and references, as well as showing the backstories of various NPCs in the game. Oh yeah, and his definition of "completionist" includes things like opening every single chest in the game.
From since he started the playthrough until he finished it, I went from understanding almost nothing he says to understanding almost everything he says, so it's been fun to see my Japanese ability progressing along with the playthrough.
It's an absolute epic run which will deepen your understanding of the game as well as the entire Zelda series and I strongly recommend people watch it.