Ammonian

The Ammonians are an advanced species hailing from the binary planets Unnamed Ammonian Mini-Neptune and Unnamed Ammonian Superearth.

Biology and appearance
The Ammonians are sentient humanoids that evolved in an ammonia instead of water environment. This caused them to function with a different chemistry than the rest of the galaxy.

Not much is known about the Ammonians appearance, due to the requirement of them having to wearing pressure suits, and is only known from information from them.

Hybrids' bodies can digest both ammonia foods, boron and carbon based, and hydrocarbons, and most are known to posses enzymes that break down oxygen containing food.

Oxygen Control
Ammonians, due to their physiology, are very susceptible to oxygen poisoning, and therefore had special enzymes that trap oxygen in stable compounds, but they still refrain from consuming or being around oxygen.

Races
The Ammonians were from two original races. One are the hydrogen breathers, who evolved on the Mini-Neptune, star road and the tall mountains of the superearth. The other are the cyanogens, who evolved in the oceans and land of the superearth.

Technology
The Ammonians are one of the most advanced species in the galaxy, due to precursor technology on their homeworld, gaining technology from the Forerunners, and avoiding the Halo event. They use both warp and slipspace for FTL travel.