Looks more like the death star than the sun. And come on, each bender has a specialty of their respective types, no mixing. Phase-changing earth is just unique enough that nobody's really tried it, I guess. It doesn't seem to have that many applications, as really anything you do with hot rock you could basically do with regular.
Remember when I said the fights were getting worse? Forget that; Su vs Lin was beautiful to watch.
Ok, with all this metalbending stuff showing up recently, metalbending itself has stopped making sense for me. Originally, Toph was able to metalbend because she could locate small impurities of earth in her metal cage and manipulate them. In the promise, she started to teach others how to metalbend, which I would have to assume she also taught her seismic sense, because you can't metalbend without sensing the earth in the metal. Lin's use of seismic sense in season 1 seemed to confirm this. So, how exactly does Korra or Bolin just pick up a meteorite and mess around with it?
Here's something else: Sato said his metal tanks were made of "pure platinum", which was "too pure" for "even Toph" to bend. By that reasoning, it seems that the periodic table of elements is understood in LoK's time. So, why can't metalbenders bend platinum? Because it's "pure metal" and not "earth"? Question is, what IS earth? In early season 1, when all the earthbenders were trapped on the floating prison, team avatar released coal used for fuel on the deck, which the earthbenders could use to fight with. Coal=Carbon, or usually at least 80% carbon. How does their bending tell the difference between carbon and platinum? The place on the periodic table? They are pretty far apart, so I guess that makes a bit of sense, but with the elements showing up, criteria for "earth" aren't really defined. Rock is mainly silicon, which is near carbon, which also makes some sense. But being able to bend carbon and silicon means like...earthbenders should be able to manipulate human tissue or glass.
Digging even deeper into this: metalbenders seem to be able to manipulate meteorites, and not regular earthbenders, but a large majority of meteorites are made of silicate materials, similar to stone. Only a few rare meteorites are made of metal, and those are usually iron or nickel. Both of those metals aren't really prevalent in "stone" or "earth"; I think we could agree that they're pretty pure, too. So why can metalbenders alter special iron meteorites that are pure metal, with no imperfections? It's as unrelated to "earth" as it could be.
Basically, the whole "you need to sense earth in metal to bend it" has stopped making sense, and the cheating of saying metalbenders can't touch heavy elements has further complicated things. Most metal is some kind of alloy of Iron anyway, which doesn't have any "earth" in it at all! You're telling me that all the metal these sculptures and cities are being made of has noticeable amounts of clay and sandstone in it? No thank you.