I am an aspiring science-fiction novelist. I am experimenting with a world I’m trying to create and I wanted a couple of expert opinions on Atmospheric composition;
53% Nitrogen 27% Oxygen 3% Xenon 15% Water Vapor 2% Carbon Dioxide
Off the bat, the air isn’t supposed to be breathable for traditional earth-based life. It is inhabited by a couple of cultures (most primitive being Neolithic hunter-gatherers, most advanced Iron Age equivalent to the Viking Age), it has a lighter gravity than earth with twice the atmosphere and I am curious what would happen to an explorer from Earth if their breathing mask was removed.
Edit: by twice the atmosphere I mean the atmosphere is twice as thick, allowing more massive creatures to fly.