There's this major thing known as ALttP Randomizer, basically, as the name implies, the items are all swapped around. And it's not just chests, NPC's and heart piece locations and even the mushroom are also randomized. There are even bomb upgrades in the item pool, as well as the half magic. You can also choose from a variety to sprites as new ones get added with every logic update. The logic never lets items be in spots that are impossible to get, like the big key in its big key chest.
There is also entrance randomizer and other variations like enemizer which can not only swap enemies, but also palettes, indoor music, enemy health/damage, etc.
You can also play from easy to insane, I suggest starting with easy or normal before you go crazy with the harder difficulties.
ALttP Randomizer also has a discord server you can join. You can find it at the website.
Credits to the creators (Veetorp, EvilAsh25, Karkat, ChristosOwens, etc.) as ALttP:R would not be possible without them (as it says on the website).