It introduces a modular magic system, where you learn spell components and make your own spells. Eventually your magic gets powerful enough that you don’t need most tools. It also adds rituals, familiars, enchantments, and some automation.
I really like that instead of introducing a lot of extra fluff, it utilizes underused Minecraft ores, mainly gold and those purple crystals.
I know many people did not, but I really enjoyed the King’s Quest reboot.