I am announced before I arrive, yet I still take many by surprise. I am given a human name, but no human can command me. I draw strength from warm oceans, and leave behind new shapes to familiar coasts. From far above, I look like a perfect spiral, but on the ground, I am anything but orderly. What am I?

A body of water that proves that isolation is safety.

English learners often misspell this word, changing it from something that is often vast and hot to something that is often small and sweet.

Without my first two, if you know how to use me, I point the way. As a whole, I envelop a certain area, so to say.

All around you I shall rest To protect your noble crest; From banners high to dungeons low, I prevent your overthrow. If a Gatherer Magician you might be, Only by air you may pass through me!