Exobiota

Explore a living alien interconnected underworld set in the fallen, decaying subterranean arcologies of the moon Midsheol. Splice your genome with specimens of biota you collect, and grow your capabilities to better survive. 
You're a diplomat's apprentice. You narrowly survived an ambush of unknown blame. Upon waking in an abandoned pre-war clinic, you're tasked with picking up the pieces of the diplomatic mission on which you were set. First you'll need to communicate with alien species, fight hostile fauna, and delve the caverns, mines and decaying underground forests beneath the moon's long dead airless surface.
Discover a Dying World
The home world of the unknowably ancient clade of intelligent species known as the Kin. Once dwellers of the surface, the sun of this moon has long been unstable. Believed to be so due to a failed stellar engineering project thousands of years ago, the moon as you know it lives on deep underground. As part of Humanity's second attempt to gain a foothold and establish meaningful diplomatic channels with the elusive Kin, it's in your power to help or hinder that tie.
Genetic Deviation
It will be in your best interest to adopt genetic adaptations that allow you to survive, marooned and out of contact with your superiors. While many opportunities to change yourself and gain non-human abilities, beware you don't lose what makes you human.
Alien Biological RPG
Your character's progression is tied to the biological materials you can get your hands on. Exploration and experimentation will be your guiding light toward a stronger character. Killing a creature might not be necessary if you can find a way to harvest what you need from it. Leverage powers to incapacitate, kill or cure sick organisms you encounter, but also to reach places within the environment that you couldn't reach before.
Will you help broker a peace between humans and the Kin, or let the region devolve into full blown war. Make your choice.