The Aliens

Not much is known about the aliens but there are some facts NASA has deduced that may help you with your task.

1. They come from a planet NASA has identified as Kepler-452b.
2. They breath nitrogen and carbon dioxide to survive.  They do not need both gasses as they are descendants of two different species from nearby planets and have adapted to live in both atmospheres.
3. They use a photosynthesis-like process to convert solar radiation to energy and thus do not need to eat organic matter.
4. They are very strong.  The gravity of their home planet is 12 m/s^2.
5. They probably don't look like this: