Nicolas "Sparth" Bouvier is the man behind the art style of Halo 5: Guardians. Currently working as Art Director at 343 industries, he's a veteran of the industry since 1997. He contributed to many games like Assassin's Creed, Halo 4 and Rage. 

Sparth's vision of sci-fi is very unique, especially in his use of color, often showing warmer hues and broader strokes than what many would expect to see in futuristic paintings. The result  is definitely amazing.

Just check it out the gallery below, and you'll probably understand why he's a perfect match for the Halo franchise (If you want to see more, you can check out Sparth's Artstation Portfolio, his own website, or his personal Tumblr). Yet, all the artwork included here is part of Sparth's personal designs, and isn't related to Halo, even is many of the paintings would fit the world of Master Chief like a glove. 

Turns out that Sparth is also lightning fast, producing stunning sketches in under 30 minutes. Below you can see a selection of his artwork that took less than half a hour to create: