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human
[Star Wars] How were Anakin, Obi-Wan, and the Separatist High Council able to breathe on Mustafar?

A thought occurred to me while watching a video discussing the surface conditions on the planet Venus, basically, if Mustafar is an entire planet covered in constant lava flows, much like our Venus in its apocalyptic one in half a billion years global subduction event...shouldn’t the air be filled with chemicals that are fatally toxic to humans and most living things in the Galaxy? I accept the Mustafarians being able to exist because the Galaxy has a wide array of both carbon-based and silicon-based life, however most inhabited/inhabitable planets seem to have at least Earth-like conditions which is why most can harbor a wide arrange of life, but the conditions of Mustafar should mean it has air quality comparable to Hadean Earth at best if not Venus at worst yeah?

In fact how are so many species able to breathe on so many different planets to begin with?
gpt
Residual atmosphere from before it was all on fire, probably helped with a little terraforming or some kind of atmosphere-in-a-bubble set up.

In Legends Mustafar was once a lush jungle planet, home to several Jedi Temples. The Sith attacked, and the battle affected the local planet's rotations in such a way that Mustafar became transformed into a fiery hellscape. 

It's also worth mentioning that the materials that are being mined on Mustafar are considered to be incredibly rare. So the atmospheric makeup may not be what one would expect from a lava planet, and besides that, there's probably quite a bit of money in keeping the planet usable, if not necessarily habitable.