A, A, Bam Ov, Animal Handling.

You are now proficient with heavy armor, which means you can wear heavy armor and a cast spells still. In order to cast sbells wearing armor, you have to be proficient in that type of armor. The nature domain lets you also charm animals and plants using channel divinity. Yet, you can make any animal or plant, which is interesting, friendly to you. So wizards choose different schools in magic, and that does sort of the same thing as cleric domains. There's other stuff like nacromancy, or a alteration, or all kinds of different stuff.