The catastrophic, intergalactic weaponry used by the alien invaders during the war created a fallout of pollution and toxins that caused severe genetic anomalies throughout humanity in the years to come.
The character concept you see in front of you describes one of the beasts left lurking around after the invasion.
This guy was demoed during class in about two hours.
Here is a recording of the Apocalyptic Mutant Character Concept: youtu.be/i7zvsDVoXTI
The video is sped up from about 2 hours down to about 15 min, and demonstrates the entire work flow from start to finish.
Check it out and enjoy the video.