People here created artist tags for bigmac966 and ian_macdonal, but it's the same person.
Here's some links to create a unified wiki for this tags ('cause I can't edit it ):
Deviantart page -> https://bigmac996.deviantart.com/
Artstation page -> https://www.artstation.com/bigmac996
page on Tumblr -> http://ianmacdonaldart.tumblr.com/